Update Gemfile: Rails 4-0-stable default, new hash syntax,
Update Gemfile: Rails 4-0-stable default, new hash syntax,

and remove the polyamorous gem (which is already specified in the
gemspec).

johan--/ransack,laserlemon/ransack,Mario245/ransack,mariorcardoso/ransack,nagyt234/ransack,activerecord-hackery/ransack,martndemus/ransack,amboxer21/ransack,praktijkindex/ransack,avit/ransack,Eric-Guo/ransack,roman-franko/ransack,reinteractive/ransack,guilleva/ransack,outstand/ransack,vaski/ransack,AndrewSwerlick/ransack