Don't require commit to be specified for a disabled build

fdroidserver/common.py

@@ -547,7 +547,7 @@ def parse_metadata(metafile, verbose=False):
         line = line.rstrip('\r\n')
         if mode == 3:
             if not any(line.startswith(s) for s in (' ', '\t')):
-                if 'commit' not in curbuild:
+                if 'commit' not in curbuild and 'disable' not in curbuild:
                     raise MetaDataException("No commit specified for {0} in {1}".format(
                         curbuild['version'], metafile.name))
                 thisinfo['builds'].append(curbuild)