* Added .requirements.txt to MANIFEST.in.
* Added an optional -S and -T args to specify the storage URL and a token.
* ssbench-master will use ST_* env vars as default values for -A, -U, -K.
* Added -v/--verbose to ssbench-master/worker.
* ssbench-master can override the scenario-specified container count (-c )
and user count (-u ) on the command-line.
* Removed ssbench-worker concurrency option and just hard-coded it to 256.
* Added back in real-time, per-result single-character progress to STDERR.
* Updated and improved README.rst