v1.6.0

PR#113 Improves fail-proof ness (thanks Matus Jasnicky)

PR#114 Raise an exception if an infinite loop occurs (thanks Matus Jasnicky)

PR#116 Fixes unpack_wide function to accomodate changes in Python3 (thanks Josh Grunzweig)

PR#117 Improve detection of infinite loop from _typeseq_iter (thanks Matus Jasnicky)

PR#124 Manifest.py has multiple bugs when using the cli function and is not usable (thanks Connor E. Basile)

PR#125 Get the first element of tuple before interacting with it in the get_requires method (thanks Daniel García Frías)

PR#126 Fixes invalid sentinel for file iteration (thanks Sergey Ilinykh))

PR#127 M2Crypto becomes an optional dependency. The crypto module adds a new crypto_enabled function to check this, and a CryptoDisabled exception for API calls which are invoked when M2Crypto isn't available.

Change Cheetah3 pip dependency for CT3

moves to tox for unittesting, flake8, and bandit integration