Move deprecated methods into a new Guard::DeprecatedMethods module
Deprecate Guard.guards in favor of Guard.plugins
Deprecated Guard.add_guard in favor of Guard.add_plugin
Move Guard main commands (start, stop, reload, run_all, pause…) to a new Guard::Commander module
Improve interactor code and specs
Improve overall documentation consistency
Improved README
Improve notifiers code
Fix gemspec & simplify Gemfile