Model Changes for Infra State Machine Placement

https://bugzilla.redhat.com/show_bug.cgi?id=1129748

This is just the code changes in the CFME models
Automate DB changes for Infra State Machine Placement

https://bugzilla.redhat.com/show_bug.cgi?id=1129748

This just has the DB changes related to Automate State Machine
calling Placement
Merge pull request #384 from mkanoor/infrastructure_best_fit

Support for running placement of infrastructure vms from Automate State Machine