Allow user to update profile as part of the OAuth flow

- created text fields in the authorizations page that correspond to profile fields from requested scopes
- disabled text fields that are already filled out (can change styling so that they don't look like text fields)
- use profile.update_attributes with whitelisted profile hash to save fields
- model, controller, and capybara tests where appropriate
- removed a few unused methods
- TODO: organize FIELDS and METHODS constants in profile so it's easier to access them elsewhere
capture profile validation failure and display errors

Redirect back to authorization page when profile.update_attributes(...) fails. Call the redirect with the same OAuth authorization params and set flash message to error.
Merge branch 'devel' into feature/update-profile-in-oauth-flow

Conflicts:
	spec/features/doorkeeper/oauth_spec.rb
Minor refactor to profile save in AuthorizationsController
Merge branch 'devel' into feature/update-profile-in-oauth-flow

Conflicts:
	app/helpers/oauth_helper.rb
	app/views/doorkeeper/authorizations/new.html.erb
	spec/features/doorkeeper/oauth_spec.rb
	spec/support/page_objects/oauth2/authorization_page.rb