unit coverage for wrong-case
Implement a pip self-check with to determine when it's out of date.

Initial work cribbed from PR 1214.
Merge pull request #2032 from bukzor/buck-coverage-1

unit coverage for wrong-case
Fix for Python 3.x, Refactor, and small changes
Fix compatability with Python 2.6
Fix on PyPy
Fix pep8 tests
Merge pull request #2049 from dstufft/pip-version-check-redux

pip version check redux
Partial checkpoint of work to add --user to pip list