Bugfix class WriteWorker, to enable multiple instances with different remote stores, as needed in the test cases
Refactor rename class _WriteWorkerProcesses to WriteWorkerProcesses
Add parameter pool to constructor of class WriteWorker, to use a process pool of type WriteWorkerProcesses
Adapt subclass ChunkWriteWorker of class WriteWorker, add parameter pool to the constructor of ChunkWriteWorker
Adapt classes StoreSyncThread, and ChunkStoreSyncThread, to conform with the signature change of WriteWorker
Update CHANGELOG with new version
Update setup.py with new version