OAK-524 : Implement PrincipalManager#getPrincipals(int searchType)
OAK-545 : PrincipalManager#findPrincipal should not search for exact name

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1431287 13f79535-47bb-0310-9956-ffa450edef68