Pure angular login

Sorry for the mess. I am new to GitHub and did not stay on master while working on these changes.

I added the following changes (in short).

- Login system does not depend on express routes (frontend). 100% AngularJS + PassportJS. Unit Tests included (httpInterceptor test missing). On login/register page currently only Facebook / Google / Twitter Login. Support of the rest was not removed, just hidden from view.
- Uses SCSS instead of CSS. Grunt compiles SCSS automatically
- Uses Angular UI-Router instead of ng-route
- Updated nodemon to current version 2.0
- 'Updated' security: old window.user exposed hashed password and email address.
- animate.css for failure message
- font-awesome added