Added travis ci support
Merge branch 'master' of github.com:gngdb/markdown-pprint

Merge upstream commits made on gav's copy
Converted parser from deprecated optparse to argparse
Added 3.3 testing to travis.yml to get push to test travis integration works
Removed 3.3 from .travis.yml and added build status button to readme
Merge pull request #6 from fmaguire/master

Travis integration and CLI parser upgrade