Improve the "about" page

Add a link to the git hooks documentation which gives more context
about what is "not supported". Add links to the configuration and
list of supported hooks.

Change-Id: Ica629c70334951124bce439a4672fa28b40a2d61
diff --git a/src/main/resources/Documentation/about.md b/src/main/resources/Documentation/about.md
index 17c7998..b8b2e91 100644
--- a/src/main/resources/Documentation/about.md
+++ b/src/main/resources/Documentation/about.md
@@ -1,2 +1,8 @@
-Gerrit does not run any of the standard git hooks in the repositories
-it works with, but this plugin implements its own hook mechanism.
+Gerrit does not support the [standard server-side git hooks][1] in the
+repositories it manages. This plugin adds support for custom hooks that
+can be run instead. Refer to the [configuration documentation][2] and
+[list of supported hooks][3] for details.
+
+[1]: https://git-scm.com/book/gr/v2/Customizing-Git-Git-Hooks
+[2]: config.md
+[3]: hooks.md