[WIP] (Start of) Rewrite of chef to work properly with CentOS, use rbenv...

.../ruby-build, support multiple runs/upgrades and generally be more resilient.

Known Issues:
* Lots of commented bits and pieces need cleanup
* Foreman export doesn't seem to work amazingly: Will start huginn service properly (i think), but unicorn processes are left running when we stop it?
* Still using 'old method' for sudoers (Chef sudo cookbook doesn't seem to want to work :S)
* Sensitive env variables are shown in `ps aux` for foreman tasks

TODO:
* Make more bits configurable (see attributes/default.rb)
* Continue adding support for setting .env configuration from chef role
* Fix foreman/unicorn issues
* Cleanup/remove huginn_development cookbook and modify it to work from just the huginn_development role
* Test a fresh install on a clean/new server (For CentOS AND other platforms)