Add tests for creating and hashing worker instances.
Add tests for creating and hashing worker instances.

harrissoerja/vumi,TouK/vumi,vishwaprakashmishra/xmatrix,TouK/vumi,vishwaprakashmishra/xmatrix,vishwaprakashmishra/xmatrix,harrissoerja/vumi,harrissoerja/vumi,TouK/vumi