I have removed gluezilla from the [extra] repository. gluezilla was a
C#/Mono-Wrapper for xulrunner, but it seems that the project itself
isn't updated anymore since nearly 2 years now. It won't compile with
the newest xulrunner and it was on the list of rebuilds for libpng1.5.
No other package requires gluezilla, so this doesn't have any
effect on any other package in our repos.