Add Categories entry to the .desktop file

Author: Nick Andrik <nick.andrik@gmail.com>
Index: b/acetoneiso/menu/AcetoneISO.desktop
===================================================================
--- a/acetoneiso/menu/AcetoneISO.desktop
+++ b/acetoneiso/menu/AcetoneISO.desktop
@@ -4,6 +4,7 @@
 Icon=Acetino2
 MimeType=application/x-iso;
 Name=AcetoneISO
+Categories=Utility;
 GenericName=CD/DVD image manipulator
 GenericName[it]=Strumenti per immagini CD/DVD
 GenericName[de]=CD/DVD-Abbildmanager
