Check that the HOME environment variable is set

A lot of things we do in the install script rely on this.
Add git remove to track deleted files
Merge pull request #2003 from MirantisDellCrowbar/fix/git_pip-cache/master

Fix: git workaround for cache
Added cisco-ucs barclamp to openstack-os-build
Merge pull request #2004 from vuntz/home-check

Check that the HOME environment variable is set
Merge pull request #2005 from tboerger/feature/cisco-ucs

Added cisco-ucs barclamp to openstack-os-build