Generate Heat templates

The current situation of requiring set of heat templates for each COE and for each OS creates a great amount of duplication in the heat templates. To alleviate this problem we can create heat templates in jinja2 to programmatically build a heat template based on COE type and OS. This will dramatically reduce the repetition Magnum has across heat templates.

A tool will be created that generates heat templates for the various combinations of OS distributions and COE. This will enable cloud operators to easily update raw heat templates for their own deployments, but also allow the Magnum to reduce its maintenance overhead. These templates will be generated by running 'tox -egentmpl', if a change is made to the jinja2 templates by the user this will need to be re run. The heat templates will be removed from the magnum repo and generated at integration time or when needed.

If the templates are found on the file path the templates will not be generated, if not found then Magnum will generate the files at runtime and store them to the correct file path.

Work will initially be needed to unify the style of the templates to make it easier to move to this set of generated templates, and then work on creating the tooling and the template files will occur.