Merge pull request #29 from mposolda/social

KEYCLOAK-42: Typo in RealmModel.importRealm causing that bad required credential type could be imported
KEYCLOAK-44
Add configuration of TOTP to registration
Added SocialLink, which represents binding between User and his social username for particular socialProvider
Added realm option automaticRegistrationAfterSocialLogin to specify whether user is automatically registered after social login or whether he needs to confirm registration data
Basic social flow with automatic registration and non-duplicated username
Basic flow with user registration with prefilled attributes from social