Added get/set_persistence
Fixed the name of get/set_persistence to get/set_entity_persistence
Merge pull request #141 from ACzChef/master

Added get/set_persistence
made get/set_entity_persistence booleans make more sense
Merge pull request #142 from ACzChef/master

made get/set_entity_persistence booleans make more sense
Dev drop
Merge origin/master
Expaned on the documentation for is_integral/is_numeric, and added unit tests for round().
Fixed small error with messaging.
Merged in from master