updates-proxy: allow xz compressed metadata (fc21)

network/filter-updates

@@ -1,6 +1,6 @@
 # Yum filters
 # -----------------------------------------------------------------------------
-/repodata/[A-Za-z0-9-]*\(primary\|filelists\|comps\(-[a-z0-9]*\)\?\|other\|prestodelta\|updateinfo\|pkgtags\)\.\(sqlite\|xml\)\(\.bz2\|\.gz\)\?$
+/repodata/[A-Za-z0-9-]*\(primary\|filelists\|comps\(-[a-z0-9]*\)\?\|other\|prestodelta\|updateinfo\|pkgtags\)\.\(sqlite\|xml\)\(\.bz2\|\.gz\|\.xz\)\?$
 /repodata/repomd\.xml$
 \.rpm$
 \.drpm$