- BuildIgnore python[23]-pyparsing: python-packaging requires it
for some actions it could perform, but we don't make use of these
here. Ignoring this dependency allows us to break open a
BuildCycle.

- Update to version 2.3.0+git.1546912853.bf348d6:
* Update CHANGES to include note on fixing issue #65; generalized the note about the decaf language example; added sample code from the statemachine examples.
* Unit test to test fix for issue #65
* Fix inconsistency between Keyword(caseless=True) and CaselessKeyword (issue #65)
* Fix typo: 'chemcialFormulas.py' -> 'chemicalFormulas.py'
* Convert exception logging to use ParseException.explain()
* Add experimental ParseException.explain() method, to return a multiline string showing the parse expressions leading to a parsing failure
* Clean up CHANGES notes for new examples
* Add document signoff and library book state examples;
* Update statemachine demo code to Py3
* Update Lucene grammar example, but remove from Travis-CI acceptance scripts