revert to AbstractDAO
add transaction propagation MANDATORY on new property repository's methods
re-factoring
develop persistence context controller
develop DocumentsRepository
add FlushMode
develop FlushModeResolver
add QueryDefinition and its default realization
develop QueryDefinitionsRepository and its default implementation
split StatementQueryDefinition and NamedQueryDefinition
develop DefaultNamedQueryDefinitionRepository
ORM layer module re-engineering
NamedQueryDefinition re-factoring
develop OrdersRepository implementation
develop UsersRepository implementation