Alias: fix ^!alias$ == crash bug

BUGS

@@ -13,7 +13,6 @@ dr.botzo --- BUGS
      ends up sending the reply to the bot itself (as that is the target of the incoming
      privmsg, same as in a channel, but the bot is supposed to overwrite the nick case
      with the sender's)
-   * line saying only '!alias' == crash
    * if a trigger text replacement happens, the original text is unavailable to modules
      f.x., saying (this text will be replaced with a trigger)++ will cause (replacement)++
      to be seen by the karma module. fix: pass along the original text as an argument

DrBotIRC.py

@@ -162,6 +162,10 @@ class DrBotIRC(irclib.IRC):
 
         # first see if the aliases are being directly manipulated via add/remove
         whats = what.split(' ')
+
+        if len(whats) <= 1:
+            return
+
         try:
             if whats[0] == '!alias' and whats[1] == 'add' and len(whats) >= 4:
                 if not self.config.has_section('Alias'):