[glib] gerror: Add an extra heading to the GError documentation

[Philip Withnall <pwithnall src gnome org>]

commit 5ceaeef832fb595d1d5117524937b15c892cbd75
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Fri Jan 16 08:32:20 2015 +0000

    gerror: Add an extra heading to the GError documentation
    
    This means that the top of the documentation can link forward to this
    important section, and random people on the internet can link directly
    to it on developer.gnome.org.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=743011

 glib/gerror.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/glib/gerror.c b/glib/gerror.c
index 96a6036..1722f20 100644
--- a/glib/gerror.c
+++ b/glib/gerror.c
@@ -30,8 +30,8 @@
  * GLib provides a standard method of reporting errors from a called
  * function to the calling code. (This is the same problem solved by
  * exceptions in other languages.) It's important to understand that
- * this method is both a data type (the #GError struct) and a set of
- * rules. If you use #GError incorrectly, then your code will not
+ * this method is both a data type (the #GError struct) and a [set of
+ * rules][gerror-rules]. If you use #GError incorrectly, then your code will not
  * properly interoperate with other code that uses #GError, and users
  * of your API will probably get confused.
  *
@@ -279,6 +279,8 @@
  *   instead treat any unrecognized error code as equivalent to
  *   FAILED.
  *
+ * ## Rules for use of #GError # {#gerror-rules}
+ *
  * Summary of rules for use of #GError:
  *
  * - Do not report programming errors via #GError.