move rubocop loading error to the check
move checks to plugins
stop using Bundler, fix dependencies, improve loading warning
adjust naming for conventions used in pluginator, fix tests
use full_gem_path for specification path
use newer pluginator with support for 1.9.3
remove Check from name when already in Checks namespace, improve loading
ignore Gemfile.lock - it should not be commited in gems
try to fix rubinius dependencies
Merge branch 'master' into feature/plugins

Conflicts:
	Gemfile
	Gemfile.lock
	lib/pre-commit/checks.rb
add rubysl-open3 and rubysl-stringio for rubinius
drop nested module definition
Merge pull request #104 from jish/feature/plugins

add support plugins