TTML2 Validation Tests

I have completed populating the ttml2-tests [1] repository with 518
validation functionality tests, of which 195 test valid content and 323
test invalid content. These tests cover ALL new features (labeled with
standard feature designations) defined in TTML2 that were not defined or
equivalent to a labelled TTML1 feature. At least one test covers each new
feature as indicated in TTML2 Tests by Feature [2].

An implementation of a TTML2 validation processor passes this test suite if
it does NOT report any false negatives for the 195 valid content tests. It
addition, it should (but is not required to) NOT report any false positives
for the 323 invalid content tests.

In its present form, TTV [3] reports no false negatives and no false
positives for all 518 tests, and, therefore, passes the test suite. See
attached maven logs and surefire-report (junit) output files.

[1] https://github.com/w3c/ttml2-tests
[2]
https://drive.google.com/open?id=1nunAY0F0bxL0nZDng2VxmWHv7i2RyAIvKQwDiiVzooc
[3] https://github.com/skynav/ttt/tree/master/ttt-ttv