Gem updates
Bump to 2.1.1.
Update readme
Update README.md
closes #1111 and allows for configurable su shell for those using rvm in production
Merge pull request #1112 from concerto/service-shell-tweak

closes #1111 and allows for configurable su shell for those using rvm in...
Merge branch 'master' of git://github.com/concerto/concerto into rails-4

* 'master' of git://github.com/concerto/concerto:
  closes #1111 and allows for configurable su shell for those using rvm in production
  Update README.md
  Update readme
  Bump to 2.1.1.
  Gem updates

Conflicts:
	Gemfile-plugins
	Gemfile.lock