Fix PyParsing dependency

Peg the version of PyParsing based on the Python version,
at least until cmd2 can be updated with a release that does
the same.

Change-Id: Ib9a7aad26ad8247706db16ee52cc385678062c51
Signed-off-by: Doug Hellmann <doug.hellmann@dreamhost.com>
prepare for 1.3.1 release

Change-Id: I809abaef23be9e71b3a9a7f7546bf73728deb6a2
Signed-off-by: Doug Hellmann <doug.hellmann@dreamhost.com>