noting more TODOs
Ported over configure_slaves.feature
Added a default SlaveProvider that creates slaves locally
bind to SlaveProvider as a provider
bug fix
bug fix
Moving slave related code into a separate mixin
in Jenkins, SSH support is a ComputerLauncher, not a Slave.

So it's incorrect to define it as a subtype of Slave.
It is just a dumb slave that's configured bit differently.
SlaveController tends to touch WebDriver. Extend from CapybaraPortingLayer.