This change removes PyKMIP support for Python2.6. The last release
of Python2.6 occurred in October 2013, over 3 years ago. It also
does not support security features needed to use PyKMIP according
to best practices. This change drops tox and TravisCI settings for
Python2.6 and updates setup to no longer categorize the library as
Python2.6 compliant. The README has been updated accordingly.
Closes#116
This change removes coveralls integration from PyKMIP, specifically
the tox and TravisCI configuration files. codecov will be the
primary coverage tool used going forward.