Include required antl3 library and check if datastore is available
Include required antl3 library and check if datastore is available

The datastore is checked for availability before requesting it to
be cleared. This is because gaeftest uses its own method for ensuring
no leakage of data by providing a temporary file as the backend.

Reviewed by: Sverre Rabbelier

MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging