Added roles_users model to handle user roles relationship with cancan gem, modified seed.rb to handle all pre-populate data
Removed role, roles_users models and uses rolify gem instead

Removed role, roles_users models and uses rolify gem instead to handle
role management along with cancan gem
Added gmaps4rails gem to integrate Google Maps, and removed old roles_users model, controller, and view

Added gmaps4rails gem and geocoder gem to test integrate Google Map