Deployment settings wiring to models

This makes the wizard work
Deployment page and link + search
Fixes the new deployment link, fixes deployments listing condition
Delete mechanism for deployments utilizing Foreman action button.

Destroy method

Success alert

Engine fix for extensions

Hostgroup child delete.

Fix delete cascade
Update Deployment::Deploy action to use new model
Remove nested load_paths to avoid problems

moving concerns to its namespace
#destroy is always true

or it raises on error
Fix creation of nested Hostgroups
Add check to remove the nest method when upgraded to 1.5
Somehow the stylesheets modification for engine went missing.
Fix hostgroup lookup
Do not use deployment name in hostgroup name

to remove the duplication from
"deploy-default/OS/OS: Controller (Neutron)"
reducing it to
"deploy-default/OS/Controller (Neutron)"
Redirect to deployment detail after wizard finishes

Wizard controller cleanup, point cancel button in wizard to deployment destroy
Do not fail when on 1.5-develop version
Revert "Somehow the stylesheets modification for engine went missing."

This reverts commit 3467699237cd15fba499b6395c80ac4c416db8df.
Refactor DeploymentRoleHostgroup and LayoutRole into a single join model
augment migration with actual data fix

Prior migration worked if there was no data, but failed if there was
a Deployment. This works with or without a Deployment.
Use host stats to check host ready