New Actor API

This is a complete rewrite of most of the actors (especially SSH), transfer mechanism, and the Installer/Actor internal API...  Passing the installers to the actors seems so logical to me... you could say separation of concern, blah... but I think it's the actors concern to install (and verify) things, so it makes sense to me to just pass them the installer or Verifyier and say "install [Apt]", "install [Transfer]", etc... and it's the only way (or the easy way?) to get to my next big feature of tuning the installers on a host-by-host basis to allow commands (and templates) to setup each host differently based on variables defined in the roles.

The actors know about the roles and hosts... so they need to be able to regenerate the installers (maybe later packages) dynamically per host (subbing variables, potentially changing logic, etc)... that's the big feature I'm missing that I think will make me mostly happy.

I'm submitting this for review and testing (not merging!)... I need to test it a bit more myself (likely beef up the tests) and I haven't done any testing of the Vlad code... it's just what looks correct based on what was there before.

Would love any thoughts and feedback.  Anyone who can test that'd be great.