First pass at mobile phone number confirmation

- Create a class to store profile confirmation data
- Create a controller to manage mobile phone confirmation
- Create an integration test for mobile confirmation flow
- TODO: entry and exit from flow
- TODO: token invalidation (delete? tag as invalidated) and expiry
Rename ProfileConfirmations to MobileConfirmations

We don't need this class to be general to all profile fields
Mobile Confirmation

- Renamed controllere to MobileRecoveriesController (still hate the name, though ... )
- Added a cancel route to controller
- Work on model to regenerate tokens, use 6 digit codes, send SMS
- Set up Twilio for SMS with RSpec support
add bundler caching to .travis.yml
Only send token once

Clear out raw token on send and require a raw token to send an SMS. This will make it so that we only send an SMS when a new token is created.
Merge remote-tracking branch 'origin/devel' into feature/mobile_phone_confirmation
Create Account with Google should redirect to Mobile COnfirmation

After creating an account with Google's OAuth2, redirect the user to the mobile recovery page. This required some refactoring to User to break the find_or_create_from_omniauth into two methods (find and create ...).
Welcome page should have auto-redirect

- Create auto redirect for welcome page.
- Set default redirect to profile page instead of root.
destory mobile confirmation when mobile number changes
Merge remote-tracking branch 'origin/devel' into feature/mobile_phone_confirmation

Conflicts:
	app/models/user.rb
	config/routes.rb
	spec/models/user_spec.rb
remove commented out code
Clean up recoveries controller

- some route/action cleanup
- i18n.t(...) some stuff
- create a welcome layout that we can render text into
I18n.t for token sms message
Merge remote-tracking branch 'origin/devel' into feature/mobile_phone_confirmation

Conflicts:
	app/models/user.rb
	spec/models/user_spec.rb
Merge pull request #281 from 18F/feature/mobile_phone_confirmation

Mobile phone number confirmation