Refresh heat-cfntools element

- If Fedora, remove the packaged heat-cfntools
- Follow the same setuptools/pbr pattern as os-*-tools
- Specify pip install --pre so that local git built packages will be
  installed if available. It should be possible to always specify
  --pre since public repos do not have snapshot release packages for
  heat-cfntools
- Upgrade the virtualenv installed pip to the latest released pip.
  This is in preperation for the release of pip-1.5.7 which has
  fixes for related-bug: #1301220

Change-Id: I6441f6f78bfb111f7446362d97a2eddc3c51a99f
Merge "Refresh heat-cfntools element"