Ensure user data is maintained even when registration form fails

Fixes #128

Conflicts:
	app/views/spree/user_registrations/new.html.erb
Depend on 2.2.0.beta
Bump to selenium-webdriver 2.35.1

Otherwise we get a 'cannot load such file -- zip/zip' error on CI
Move dependencies into Gemfile, as its easier syntax
Use form_for resource in user_registrations/new.html.erb so the form always gets the right object
Add Turkish translation

Fixes #129
Use correct translation for 'back to store' link

Fixes #130
hardcode to current_user
Update engine.rb
use Spree.user_class instead of Spree::User
use Spree.user_class instead of Spree::User
use Spree.user_class.table_name for table name
override model_class
use Spree.user_class
Merge branch 'master' of github.com:mguymon/spree_auth_devise