Merge pull request #55 from brucehoff/develop

SYNR-398 and part of SYNR-358
Merge pull request #56 from brucehoff/develop

follow up from code review
added tests for File entity commands.  supporting code to follow
switched from composition to inheritance; added first round of File tests
SYNR-358
SYNR-358 all tests pass
Merge branch 'SYNR-358' into develop