Cwltest

fix Nonetype not iterable error 23 by kapilkd13
only use non-standard opts for cwltool under OS X 26 by mr-c
relax the typing module version requirement 27 by mr-c
avoid using exception.message, not necessarily available in python 3 30 by kapilkd13
Add lock around mkdtemp, which seems to be thread-unsafe 28 by tetron and mr-c
Add `classname` category to specify Python run time version in XML output file 33 by manu-chroma
Build a universal python 2+3 wheel 45b57b098a9b79b97b8fee43a57251926d59c44b by mr-c

Add failure info to the jUnit XML report 15 by bosonogi
When --verbose arg is used, don't capture stderr 17 by buchanae
Set failure message for failed test case 18 by bosonogi
Added additional conformance test arguments feature. 19 by halilozercan
Python 3 support 20 by manu-chroma
typing module dependency update 21 by mr-c & requires
add release test, MANIFEST.in, and fix Makefile 22 by mr-c