add usage

client/djrandom_client/client.py

@@ -64,7 +64,7 @@ def run_client(server_url, music_dir, api_key, run_once, bwlimit):
 
 
 def main():
-    parser = optparse.OptionParser()
+    parser = optparse.OptionParser(usage='%prog [<OPTIONS>]')
     parser.add_option('--api_key',
                       help='Your API key')
     parser.add_option('--once', action='store_true',