QuoteGrabs: Prevent quote grabs from queries.

Signed-off-by: James McCoy <vega.james@gmail.com>

plugins/QuoteGrabs/plugin.py

@@ -253,7 +253,7 @@ class QuoteGrabs(callbacks.Plugin):
         # opposed to channel which is used to determine which db to store the
         # quote in
         chan = msg.args[0]
-        if chan is None:
+        if chan is None or not irc.isChannel(chan):
             raise callbacks.ArgumentError
         if ircutils.nickEqual(nick, msg.nick):
             irc.error('You can\'t quote grab yourself.', Raise=True)