DATACMNS-530 - Improve JavaDoc for RepositoryConfigurationSourceSupport.

Removed misleading JavaDoc.

Original pull request: #97.
DATACMNS-577 - Improved JavaDoc on QueryDslPredicateExecutor.

Clarified return values if predicates don't match or return multiple results (for the findOne(…) method). Copied summary to the @return tag.

Original pull request: #96.