Excluding the docs target folder from flake8

Artifacts of the docbook build creates a target folder that will
cause the pep8 tox job to complain about the build artifacts
a bunch of failures.

Change-Id: I4cf22876504d6014ece74e58877ba8ced13f2260
Update from global requirements

Add argparse module, update pbr six python-keystoneclient modules version

Change-Id: I650348a36f7bad2091c99d83d71d039dc11b93ee
Closes-Bug: #1334785
Refactor json validator

* Changed the rest of the exception raising to use the _assert_validity
  function.
* Introduced minimum set of required  names secret refs in containers.
  (for both rsa and certificates).
* Added tests regarding these required names.

Change-Id: I31d8f254674a601cb241a7ad1bd1696d6baab3aa
Merge "Refactor json validator"
Merge "Update from global requirements"
Merge "Excluding the docs target folder from flake8"