OAK-1984 Repository.login(creds).getUserId() should return the 'real' user's id.

- adding test case

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1612870 13f79535-47bb-0310-9956-ffa450edef68
OAK-1985 TokenLoginModule can't handle case insensitive userids

- adding test case

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1612873 13f79535-47bb-0310-9956-ffa450edef68