Maintain hostgroup selection after assign host

This patch updates the deployment show page to maintain the selected
HostGroup after a the user selects the "Assign / Unassign" button.
Previous behaviour reset the selected Hostgroup to the first Hostgroup
listed.
Merge pull request #126 from mtaylor/hostgroup_selection

Maintain hostgroup selection after assign host
Add weights to provisioning and configuration actions

so a host is no longer showing as 50% done just after reboot
Merge pull request #127 from pitr-ch/master

Add weights to provisioning and configuration actions