Fix stupid bug: when migrating these tests from the Zope repository, the names of the test methods were not changed from the Zope-standard "check" names to the Python-standard "test_" names, so the tests were not actually being run.
Fix stupid bug: when migrating these tests from the Zope repository, the
names of the test methods were not changed from the Zope-standard "check"
names to the Python-standard "test_" names, so the tests were not actually
being run.

Added test of hexadecimal character references as a regression check for
SF bug #445196.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator