[gnome-music] Add a missing tag in the AppData file

[Richard Hughes <rhughes src gnome org>]

commit 207a52ccff0b47edbc72697bb0447272b8f1101f
Author: Richard Hughes <richard hughsie com>
Date:   Fri Jan 22 17:13:44 2016 +0000

    Add a missing tag in the AppData file

 data/gnome-music.appdata.xml.in |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/data/gnome-music.appdata.xml.in b/data/gnome-music.appdata.xml.in
index beae327..1c2768e 100644
--- a/data/gnome-music.appdata.xml.in
+++ b/data/gnome-music.appdata.xml.in
@@ -12,6 +12,7 @@
  <screenshots>
   <screenshot type="default" width="750" 
height="469">http://www.omgubuntu.co.uk/wp-content/uploads/2013/08/music_album.jpeg</screenshot>
  </screenshots>
+ <project_group>GNOME</project_group>
  <url type="homepage">https://wiki.gnome.org/Apps/Music</url>
  <updatecontact>seif lotfy com</updatecontact>
 </application>