Revert "Default repo manifest settings in git config"

This reverts commit ee1c2f5717.

This breaks a lot of buildbot systems. Rolling it back for now
until we can understand what the breakage was and how to fix it.

repo

@@ -28,7 +28,7 @@ if __name__ == '__main__':
 del magic
 
 # increment this whenever we make important changes to this script
-VERSION = (1, 14)
+VERSION = (1, 13)
 
 # increment this if the MAINTAINER_KEYS block is modified
 KEYRING_VERSION = (1,0)
@@ -154,7 +154,7 @@ def _Init(args):
   """Installs repo by cloning it over the network.
   """
   opt, args = init_optparse.parse_args(args)
-  if args:
+  if args or not opt.manifest_url:
     init_optparse.print_usage()
     sys.exit(1)