mime library description

R=mcampione@google.com

Review URL: https://codereview.chromium.org//23419003

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/mime@26713 260f80e4-7a28-3924-810f-c04153c831b5
diff --git a/lib/mime.dart b/lib/mime.dart
index 44c6cad..652aa85 100644
--- a/lib/mime.dart
+++ b/lib/mime.dart
@@ -2,6 +2,16 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+/**
+ * Help for working with file format identifiers
+ * such as `text/html` and `image/png`.
+ *
+ * More details, including a list of types, are in the Wikipedia article
+ * [Internet media type](http://en.wikipedia.org/wiki/Internet_media_type).
+ * For information on installing and importing this library, see the
+ * [mime package on pub.dartlang.org]
+ * (http://pub.dartlang.org/packages/mime).
+ */
 library mime;
 
 import 'dart:async';