Use Zeus via aliases, rake

* Create `rake` function and `rk` alias.
* Add `z` alias for `zeus`.
* Alias `migrate` to `m` given how common a task it is.
Pass arguments from rspec shell function when not using zeus

* Non-zeus path didn't pass arguments, so it just ran `rspec`
Run reek on app by default.
Merge with thoughtbot.
Merge branch 'upstream/master'

Merging with thoughtbot.