Temporal: added flag to be able to perform overwrite() instead of save() on temporal models
Merge branch 'temp_hack_for_cascade_save_temporal' of https://github.com/juanserra/orm into temp_hack_for_cascade_save_temporal
Merge pull request #360 from juanserra/temp_hack_for_cascade_save_temporal

Added flag to perform overwrite instead of save on temporal models