Have coveralls only measure opaque_keys module
Merge pull request #7 from edx/sarina/adjust-coverage

Have coveralls only measure opaque_keys module
Keys remember whether to use deprecated syntax

and the deprecated key handler registers itself with the base key type
LMS-2752
Increased test coverage
fixup! Keys remember whether to use deprecated syntax
fixup! Increased test coverage
fixup! Keys remember whether to use deprecated syntax
Add more tests for opaque-keys
fixup! Add more tests for opaque-keys