bot: capture exceptions, try to report on them

it beats crashing, probably

ircbot/bot.py

@@ -144,6 +144,7 @@ class DrReactor(irc.client.Reactor):
         Also supports regex handlers.
         """
 
+        try:
             log.debug("EVENT: e[%s] s[%s] t[%s] a[%s]", event.type, event.source,
                       event.target, event.arguments)
 
@@ -189,6 +190,10 @@ class DrReactor(irc.client.Reactor):
                     result = handler.callback(connection, event)
                     if result == "NO MORE":
                         return
+        except Exception as ex:
+            log.error("caught exception!")
+            log.exception(ex)
+            connection.privmsg(event.target, str(ex))
 
     def try_recursion(self, connection, event):
         """Scan message for subcommands to execute and use as part of this command.