Add strong parameters on rails 3.2
remove protected_attributes, and bring in strong_param behavior

Closes https://github.com/rubygems/rubygems.org/pull/664.

Conflicts:
	Gemfile.lock
	app/controllers/sessions_controller.rb
	app/controllers/stats_controller.rb
	app/models/dependency.rb
	app/models/rubyforger.rb
	app/models/user.rb
Update params_user list

Remove gittip_username
Make signup use strong_parameters
DRY user permit attrs
Merge pull request #802 from arthurnn/strong_params

Strong params