Remove a couple of old comments

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

omnibot/bot.py

@@ -164,10 +164,8 @@ class Bot:
             )
 
     async def keepalive(self):
-        # loop while we're connected, check every second
         await self.__quitting.wait()
         log.info("Shutting down gracefully")
-        # TODO: unload modules
         await asyncio.gather(
             *[plugin.on_unload(self.connection) for plugin in self.plugins]
         )