Simplification and changes to be able to install bash-it globally
Allow a custom fork of bash-it

Since the bash-it maintainer isn't very fast in approving theme pull requests, i needed my fork and not the main bash-it repository. So i moved the repo url to the attributes file
This version limitation is more a hassle than a benefit, but this might be personal preference
Re-enable version limitation
Merge pull request #179 from roderik/improvement/bash-it

Globally installed bash-it