Disable, stop, and remove postfix

With postfix still installed and exim set as the mta in alternatives,
things still seem wonky. Removing postfix entirely before we set the
alternative mta.

Fixes #97
Merge pull request #104 from claco/issue-97

Merged automatically by jenkins after successful build test
First pass of arbitrary configs

closes #92
Rename .chef folder to .chef-vagrant

Putting stuff in .chef makes knife for other people not worky. Moving
the shared folder to .chef-vagrant and using knife -c in and out of the
guests in the vagrant related things.
Merge pull request #105 from rpedde-rcbops/issue-92

Merged automatically by jenkins after successful build test
Merge pull request #106 from claco/fix-chef-hidden-directory

Merged automatically by jenkins after successful build test