[gedit] Add CONTRIBUTING.md file for the GitHub mirror

[Sébastien Wilmet <swilmet src gnome org>]

commit c4c41ae021572caf5ff8716b3c691fd83bbd76d2
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Oct 30 13:57:12 2015 +0100

    Add CONTRIBUTING.md file for the GitHub mirror
    
    As suggested on the desktop-devel-list in May 2015.

 CONTRIBUTING.md |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)
---
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..bb9714b
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,8 @@
+The GNOME contributing guidelines require patches to be forwarded to GNOME's
+Bugzilla instance hosted at https://bugzilla.gnome.org. Please do not open
+GitHub pull requests against this module as they will be ignored. More
+information is available at the following wiki page:
+
+    https://wiki.gnome.org/Sysadmin/GitHub
+
+To know how to contribute, read the README and HACKING files.