Strip leading :// from URLs to allow quick conversion of a pasted URL to calls (#1197)

* Strip leading `://` from URLs to allow quick conversion of a pasted URL to calls

Closes #1195

* Markdown lint

* Cleanup

* Cleanup

* Drop extraneous space

* Fix example

docs/README.md

@@ -482,14 +482,26 @@ The default scheme is `http://` and can be omitted from the argument:
 
 ```bash
 $ http example.org
-# => http://example.org
+# → http://example.org
 ```
 
 HTTPie also installs an `https` executable, where the default scheme is `https://`:
 
 ```bash
 $ https example.org
-# => https://example.org
+# → https://example.org
+```
+
+When you paste a URL into the terminal, you can even keep the `://` bit in the URL argument to quickly convert the URL into an HTTPie call just by adding a space after the protocol name.
+
+```bash
+$ https ://example.org
+# → https://example.org
+```
+
+```bash
+$ http ://example.org
+# → http://example.org
 ```
 
 ### Querystring parameters
@@ -1947,7 +1959,6 @@ HTTPie has the following community channels:
 - [curl](https://curl.haxx.se) — a "Swiss knife" command line tool and an exceptional library for transferring data with URLs.
 
 ### Contributing
-### Contributing
 
 See [CONTRIBUTING](https://github.com/httpie/httpie/blob/master/CONTRIBUTING.md).