changes to upgrade to spree2.2.x : update gemspec,specs, install generator to inject files in vendor director and gemfile
update gemspec and version file
add gem coffee-script in gemfile
update unified_payment gem version in gemspec for dependency
remove specs to check for mass assignment for Spree::StoreCredit
update spree wallet branch in Gemfile and dependency version on spree wallet
update unified_payments gem version in gemfile and gemspec, avoid exception at admin end for receipt by checking on xml_response, add route for post request on decline, add source view file for unifiedpaymentmethod, fix override for admin tab for unified payments, update checkout controller for update order with payment initiated
fix failing spec in checkout controller
update Gemfile and README
merging 2-2-stable in master