Group the desktop file into the Utilities folder in the GNOME
shell application overview.

diff --git a/xterm.desktop.old b/xterm.desktop
index ea23c9b..5381d02 100644
--- a/xterm.desktop.old
+++ b/xterm.desktop
@@ -39,4 +39,4 @@ Terminal=false
 Type=Application
 Encoding=UTF-8
 Icon=terminal
-Categories=System;TerminalEmulator;
+Categories=System;TerminalEmulator;X-GNOME-Utilities;