Added external authentication endpoints

 * Twitter
 * Facebook
 * Google
 * CAS
 * LDAP
Authentication init endpoints suffixed with `Redirect`
Merge pull request #5 from oaeproject/authentication-endpoints

Added external authentication endpoints
release 6.5.1-2
Add user management related functions to oae-rest
Add isGlobalAdmin and isTenantAdmin to api.user.js #createUser additionalOptions for user management
Separate createUser from createUserOnTenant