Merge pull request #676 from s0undt3ch/develop

Add missing exception import.
Remove salt-cloud depends python-yaml, it's required by salt-commmon
Merge pull request #679 from hvnsweeting/patch-1

Remove salt-cloud depends python-yaml, it's required by salt-common
Update code to work with the bootstrap script to keep temporary files. Fixes #680.

* Copied the development version of the bootstrap script while there's no stable release.