Remove binstubs options from defaults

[lucapette]

See #162

[lucapette]

oh that was fast! Thank you for merging it!

[vaz]

This is fine and all, I understand the rationale re: Rails 4, but this should not have been published in a patch-level update (0.3.1).

My god scripts have been calling the release's bin/unicorn and I just had a site die on me during a deployment because of that. mina/god/unicorn is my zero-downtime solution, it sucks to have a tool surprise me and cause a failure like that. If it was even a minor version update then it would have been my own fault for not checking the changelog, but of course I have mina locked to "~> 0.3.0".

Anyway just giving you a heads-up. It's easy to forget that "public API" includes more than just Ruby methods.