Add "changes" to quick_error.

Yamakaky · Yamakaky · commit 3003ecf7660f · 2016-11-19T01:13:00.000-05:00
diff --git a/src/quick_error.rs b/src/quick_error.rs
@@ -1,4 +1,7 @@
 // From https://github.com/tailhook/quick-error
+// Changes:
+//   - replace `impl Error` by `impl Item::description`
+//   - $imeta
 
 #[macro_export]
 macro_rules! quick_error {
