Spelling: compatibile->compatible

Change-Id: If8a444ccc55f1285aeb90de3ad0bc9d38acbaae8
Use testtools instead of unittest for base classes.

part of blueprint grizzle-testtools

Change-Id: Ic9b438b4224d945e080d1d6071742ddc47ee81ed
Merge "Spelling: compatibile->compatible"
Merge "Use testtools instead of unittest for base classes."