Adds bundler support and removes sudo_with_input

[mtylty]

I added bundler support in case RAILS_ROOT contains a Gemfile...

I've also reworked some stuff... I couldn't find sudo_with_input (except in some old gems on RubyForge) so I removed it...

I will be adding some more recipes in the future since I'll be using superdeploy alot. Would you like to be pull-requested??? :)

btw, great work! I was going to implement a thing like superdeploy by myself... :)