Add a couple blank lines.
Move `cmd/` files to `lib/git-hub.d/` and rm `cmd/`

All the files under `cmd/` were symlinked into lib anyway. No need for
this layer of abstraction.

Later, I will make a `plugin/` dir that people can just clone plugins
into and they'll work. `git-hub-irc` should be a plugin so I'll move
that as well.