Initial work on new guide

examples/guide/main2.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"os"
+	"runtime/trace"
+	"time"
+)
+
+func main() {
+	trace.Start(os.Stdout)
+	defer trace.Stop()
+
+	go b()
+	a()
+}
+
+func a() {
+	start := time.Now()
+	for time.Since(start) < time.Second {
+	}
+}
+
+func b() {
+	start := time.Now()
+	for time.Since(start) < time.Second {
+	}
+}