renames: models and controllers
updates: gem files to add spree 2.3, rails 4 and ruby 2
updates: lib folder and rake file for spree 2.3
updates: routes to use spree 2.3
updates: assets, adds new folders for spree 2.3
updates: controllers, make sure they are compatible with rails 4 and spree 2.3
updates: model and mailers to make sure they are compatible with rails 4 and spree  2.3
updates: spec files to make sure they all pass with rspec 3 expect syntax
updates: README file, adds more instructions