Use DbUnit's FilteredDataSet  to prevent foreign keys error.
Add delegate to simple-jpa handler in `withTransaction`.
Remove obsoletes methods in `SimpleJpaUtil`.
Rename variable and extracts common methods to `AstUtils`.
 Add `@AutoMerge` that will merge current entity when their method is called (inserted as last statement).
Add `isIn` operation (to represent query like `status in ('A', 'B', 'C')`) to DSL.
Add bindable `visible` property to `glazedColumn()`.