Add support for service hierarchies

For multipart service deployments, parent/child
relationships between services can now be visualized
in the 'My Services' tree view.

The visibility of child services needs to be enabled
via the "display" attribute on MiqAeServiceService
for child services to appear in the hierarchy, by
default they are hidden. Also added an explicit
method for create new Service records via automation.

https://bugzilla.redhat.com/show_bug.cgi?id=1059834
Move RBAC descendant check to TreeBuilder to consolidate duplicate code.

Follow up to https://github.com/ManageIQ/manageiq/pull/81
https://bugzilla.redhat.com/show_bug.cgi?id=1086015
Merge pull request #120 from Fryguy/fix_ui_vm_summary_2

Fix UI vm summary performance (part 2)
Merge pull request #12 from dillaman/bz1059834-service-hierarchies

Add support for service hierarchies
Automate model restructure code adjustments.

Minor pathing adjustments and expose platform category to aid the
 cloud/infra navigation.
Initial pass of the Automate model restructure.