SYNR-356: Functions parameters for provenance should be able to handle either entities or synIds
SYNR-345: Add commit like behavior to updateEnitity
moved Activity class out of client.py into its own file
SYNR-356 function parameters for provenance should be accept either entities or synIds
fixed bug in warning when no files are present in get command
added _createFileEntity method
updates based on code review
Merge pull request #30 from cbare/develop

Activities accept synapse IDs or entity objects (in singles or lists)