[WFCORE-125] Pull some changes from the model tests from EAP that were missing in WildFly.
[WFCORE-125] Add additional core model tests for additional permutations and add cache resource registrations under principal-to-group.
[WFCORE-126] First simplify the Builder / Parent interfaces and switch to abstract classes using generics.
[WFCORE-126] Update all LDAP realm tests to at least have the cache enabled.
Merge pull request #204 from darranl/WFCORE-125

[WFCORE-125] / [WFCORE-126] Unable to add LDAP cache for principal to group searches.