Get rid of the =poach <poacher> <sub-command>= sub-commands

It'll be `poach local all`, and everything that can be poached will be poached.
I am not sure if it should be `poach local all`  or just `poach local`

Also,

-   [ ] Refactor meetup poacher to have an explicit `self.end` method instead of
    emitting the end message in every sub-poacher. Check local poacher for reference.

