Update readme and add usability improvements to pykronos

Summary:
Almost done w/ documentation

Add readmeify.py, to generate markdown from readme Python scripts

Run find . -type f -name '*.py[cod]' -delete find . -type f -name '*~' -delete python ../common/readmeify.py < demo.py > README.md to generate README.md

More cleanup in makefile

More cleanup in makefile

Reviewers: usmanm, lydia

Reviewed By: usmanm

Differential Revision: http://phabricator.locu.com/D5451