make the config file argument optional.

this should probably be robustified (--config-file=foo) eventually

dr.botzo.py

@@ -69,14 +69,15 @@ class DrBotIRC(irclib.IRC):
          self.connections.append(c)
          return c
 
+config_file = 'dr.botzo.cfg'
 # check argv
-if len(sys.argv) != 2:
-    sys.exit("Needs one argument, the config filename")
+if len(sys.argv) == 2:
+    config_file = sys.argv[1]
 
 # read config file
 
 config = ConfigParser({'debug': 'false'})
-config.read(os.path.expanduser(sys.argv[1]))
+config.read(os.path.expanduser(config_file))
 
 # load necessary options
 try: