Quick workaround for accidentally clean of /home/vagrant while deploying

 stack.sh Now includes a cleanup for previous builds, and cleans
 instances path prior to install, this ends up cleaning /home/vagrant in
 the middle of the devstack install (using the module
 cookbooks/devstack) which point to /home/vagrant as default dir for
 instances directory.
Merge branch 'bvox' of github.com:bvox/vagrant_devstack