fixes hanging error on chromy exception
fixes 549 — hanging error on chromy exception
- tests failing because of a chromy error exception (not backstop error) now resolve with an error instead of bubbling up a rejection.
- incomplete test data is decorated with exception data and added to testPairs
- Chromy.cleanup is called when all chromy instances have settled
- comparison flow now guards against incomplete test data
- Comparison flow now handles TEST RUN EXCEPTIONS
- cleaned up cli report