updating readme to reflect the specific version of backbone.js that it packages
updating readme to reflect the specific version of backbone.js that it packages

ArthurN/backbone-rails,codebrew/backbone-rails,ArthurN/backbone-rails,codebrew/backbone-rails,ipmobiletech/backbone-rails,contently/backbone-rails,contently/backbone-rails,ipmobiletech/backbone-rails,ipmobiletech/backbone-rails,ArthurN/backbone-rails,codebrew/backbone-rails,contently/backbone-rails,contently/backbone-rails