Re-apply formatting to SUMMARY.md (#1429)

With the latest version of mdbook-i18n-helpers, we now have support for
formatting in the `SUMMARY.md` file. This allows us to revert the
changes made in #130 when we first introduced the translation support.

This also aligns a few headings to match the heading in the outline.
While this isn’t strictly necessary, it removes a bit of work for the
translators.

src/SUMMARY.md

@@ -1,3 +1,4 @@
+
 <!-- Keep first page as index.md to avoid giving it two names. -->
 [Welcome to Comprehensive Rust 🦀](index.md)
 - [Running the Course](running-the-course.md)
@@ -83,7 +84,7 @@
   - [Generic Functions](generics/generic-functions.md)
   - [Generic Data types](generics/generic-data.md)
   - [Trait Bounds](generics/trait-bounds.md)
-  - [Impl Trait](generics/impl-trait.md)
+  - [`impl Trait`](generics/impl-trait.md)
   - [Exercise: Generic `min`](generics/exercise.md)
     - [Solution](generics/solution.md)
 
@@ -93,19 +94,19 @@
 - [Standard Library Types](std-types.md)
   - [Standard Library](std-types/std.md)
   - [Language Docs](std-types/docs.md)
-  - [Option](std-types/option.md)
-  - [Result](std-types/result.md)
-  - [String](std-types/string.md)
-  - [Vec](std-types/vec.md)
-  - [HashMap](std-types/hashmap.md)
+  - [`Option`](std-types/option.md)
+  - [`Result`](std-types/result.md)
+  - [`String`](std-types/string.md)
+  - [`Vec`](std-types/vec.md)
+  - [`HashMap`](std-types/hashmap.md)
   - [Exercise: Counter](std-types/exercise.md)
     - [Solution](std-types/solution.md)
 - [Standard Library Traits](std-traits.md)
   - [Comparisons](std-traits/comparisons.md)
   - [Operators](std-traits/operators.md)
-  - [From and Into](std-traits/from-and-into.md)
+  - [`From` and `Into`](std-traits/from-and-into.md)
   - [Casting](std-traits/casting.md)
-  - [Read and Write](std-traits/read-and-write.md)
+  - [`Read` and `Write`](std-traits/read-and-write.md)
   - [`Default`, struct update syntax](std-traits/default.md)
   - [Closures](std-traits/closures.md)
   - [Exercise: ROT13](std-traits/exercise.md)
@@ -121,14 +122,14 @@
   - [Approaches to Memory Management](memory-management/approaches.md)
   - [Ownership](memory-management/ownership.md)
   - [Move semantics](memory-management/move.md)
-  - [Clone](memory-management/clone.md)
+  - [`Clone`](memory-management/clone.md)
   - [Copy Types](memory-management/copy-types.md)
-  - [Drop](memory-management/drop.md)
+  - [`Drop`](memory-management/drop.md)
   - [Exercise: Builder Type](memory-management/exercise.md)
     - [Solution](memory-management/solution.md)
 - [Smart Pointers](smart-pointers.md)
-  - [Box<T>](smart-pointers/box.md)
-  - [Rc](smart-pointers/rc.md)
+  - [`Box<T>`](smart-pointers/box.md)
+  - [`Rc`](smart-pointers/rc.md)
   - [Exercise: Binary Tree](smart-pointers/exercise.md)
     - [Solution](smart-pointers/solution.md)
 
@@ -156,16 +157,16 @@
 
 - [Welcome](welcome-day-4.md)
 - [Iterators](iterators.md)
-  - [Iterators](iterators/iterators.md)
-  - [IntoIterator](iterators/intoiterator.md)
-  - [FromIterator](iterators/fromiterator.md)
+  - [`Iterator`](iterators/iterator.md)
+  - [`IntoIterator`](iterators/intoiterator.md)
+  - [`FromIterator`](iterators/fromiterator.md)
   - [Exercise: Iterator Method Chaining](iterators/exercise.md)
     - [Solution](iterators/solution.md)
 - [Modules](modules.md)
   - [Modules](modules/modules.md)
   - [Filesystem Hierarchy](modules/filesystem.md)
   - [Visibility](modules/visibility.md)
-  - [use, super, self](modules/paths.md)
+  - [`use`, `super`, `self`](modules/paths.md)
   - [Exercise: Modules for the GUI Library](modules/exercise.md)
     - [Solution](modules/solution.md)
 - [Testing](testing.md)
@@ -185,9 +186,9 @@
   - [Panics](error-handling/panics.md)
   - [Try operator](error-handling/try.md)
   - [Try Conversions](error-handling/try-conversions.md)
-  - [Error Trait](error-handling/error.md)
-  - [thiserror and anyhow](error-handling/thiserror-and-anyhow.md)
-  - [Exercise: Rewriting with Result](error-handling/exercise.md)
+  - [`Error` Trait](error-handling/error.md)
+  - [`thiserror` and `anyhow`](error-handling/thiserror-and-anyhow.md)
+  - [Exercise: Rewriting with `Result`](error-handling/exercise.md)
     - [Solution](error-handling/solution.md)
 - [Unsafe Rust](unsafe-rust.md)
   - [Unsafe](unsafe-rust/unsafe.md)
@@ -278,17 +279,17 @@
 ----
 
 - [Welcome](bare-metal.md)
-- [no_std](bare-metal/no_std.md)
+- [`no_std`](bare-metal/no_std.md)
   - [A Minimal Example](bare-metal/minimal.md)
-  - [alloc](bare-metal/alloc.md)
+  - [`alloc`](bare-metal/alloc.md)
 - [Microcontrollers](bare-metal/microcontrollers.md)
   - [Raw MMIO](bare-metal/microcontrollers/mmio.md)
   - [PACs](bare-metal/microcontrollers/pacs.md)
   - [HAL Crates](bare-metal/microcontrollers/hals.md)
   - [Board Support Crates](bare-metal/microcontrollers/board-support.md)
   - [The Type State Pattern](bare-metal/microcontrollers/type-state.md)
-  - [embedded-hal](bare-metal/microcontrollers/embedded-hal.md)
-  - [probe-rs, cargo-embed](bare-metal/microcontrollers/probe-rs.md)
+  - [`embedded-hal`](bare-metal/microcontrollers/embedded-hal.md)
+  - [`probe-rs` and `cargo-embed`](bare-metal/microcontrollers/probe-rs.md)
     - [Debugging](bare-metal/microcontrollers/debugging.md)
   - [Other Projects](bare-metal/microcontrollers/other-projects.md)
 - [Exercises](exercises/bare-metal/morning.md)
@@ -313,13 +314,13 @@
   - [Exceptions](bare-metal/aps/exceptions.md)
   - [Other Projects](bare-metal/aps/other-projects.md)
 - [Useful Crates](bare-metal/useful-crates.md)
-  - [zerocopy](bare-metal/useful-crates/zerocopy.md)
-  - [aarch64-paging](bare-metal/useful-crates/aarch64-paging.md)
-  - [buddy_system_allocator](bare-metal/useful-crates/buddy_system_allocator.md)
-  - [tinyvec](bare-metal/useful-crates/tinyvec.md)
-  - [spin](bare-metal/useful-crates/spin.md)
+  - [`zerocopy`](bare-metal/useful-crates/zerocopy.md)
+  - [`aarch64-paging`](bare-metal/useful-crates/aarch64-paging.md)
+  - [`buddy_system_allocator`](bare-metal/useful-crates/buddy_system_allocator.md)
+  - [`tinyvec`](bare-metal/useful-crates/tinyvec.md)
+  - [`spin`](bare-metal/useful-crates/spin.md)
 - [Android](bare-metal/android.md)
-  - [vmbase](bare-metal/android/vmbase.md)
+  - [`vmbase`](bare-metal/android/vmbase.md)
 - [Exercises](exercises/bare-metal/afternoon.md)
   - [RTC Driver](exercises/bare-metal/rtc.md)
   - [Solutions](exercises/bare-metal/solutions-afternoon.md)
@@ -335,13 +336,13 @@
 - [Channels](concurrency/channels.md)
   - [Unbounded Channels](concurrency/channels/unbounded.md)
   - [Bounded Channels](concurrency/channels/bounded.md)
-- [Send and Sync](concurrency/send-sync.md)
-  - [Send](concurrency/send-sync/send.md)
-  - [Sync](concurrency/send-sync/sync.md)
+- [`Send` and `Sync`](concurrency/send-sync.md)
+  - [`Send`](concurrency/send-sync/send.md)
+  - [`Sync`](concurrency/send-sync/sync.md)
   - [Examples](concurrency/send-sync/examples.md)
 - [Shared State](concurrency/shared_state.md)
-  - [Arc](concurrency/shared_state/arc.md)
-  - [Mutex](concurrency/shared_state/mutex.md)
+  - [`Arc`](concurrency/shared_state/arc.md)
+  - [`Mutex`](concurrency/shared_state/mutex.md)
   - [Example](concurrency/shared_state/example.md)
 - [Exercises](exercises/concurrency/morning.md)
   - [Dining Philosophers](exercises/concurrency/dining-philosophers.md)
@@ -351,7 +352,7 @@
 # Concurrency: Afternoon
 
 - [Async Basics](async.md)
-  - [async/await](async/async-await.md)
+  - [`async`/`await`](async/async-await.md)
   - [Futures](async/futures.md)
   - [Runtimes](async/runtimes.md)
     - [Tokio](async/runtimes/tokio.md)
@@ -362,7 +363,7 @@
   - [Select](async/control-flow/select.md)
 - [Pitfalls](async/pitfalls.md)
   - [Blocking the Executor](async/pitfalls/blocking-executor.md)
-  - [Pin](async/pitfalls/pin.md)
+  - [`Pin`](async/pitfalls/pin.md)
   - [Async Traits](async/pitfalls/async-traits.md)
   - [Cancellation](async/pitfalls/cancellation.md)
 - [Exercises](exercises/concurrency/afternoon.md)

src/async/pitfalls/pin.md

@@ -1,4 +1,4 @@
-# Pin
+# `Pin`
 
 When you await a future, all local variables (that would ordinarily be stored on
 a stack frame) are instead stored in the Future for the current async block. If your
@@ -6,7 +6,7 @@ future has pointers to data on the stack, those pointers might get invalidated.
 This is unsafe.
 
 Therefore, you must guarantee that the addresses your future points to don't
-change. That is why we need to `pin` futures. Using the same future repeatedly
+change. That is why we need to "pin" futures. Using the same future repeatedly
 in a `select!` often leads to issues with pinned values.
 
 ```rust,editable,compile_fail

src/bare-metal/microcontrollers/probe-rs.md

@@ -1,4 +1,4 @@
-# `probe-rs`, `cargo-embed`
+# `probe-rs` and `cargo-embed`
 
 [probe-rs](https://probe.rs/) is a handy toolset for embedded debugging, like OpenOCD but better
 integrated.

src/iterators/iterator.md

@@ -5,7 +5,7 @@ minutes: 5
 <!-- NOTES:
 The Iterator trait and basic usage
 -->
-# Iterators
+# `Iterator`
 
 The [`Iterator`][1] trait supports iterating over values in a collection. It
 requires a `next` method and provides lots of methods. Many standard library types