Don't manipulate LoadBalancer template in-place

When autoscaling reloads a LoadBalancer, it adjusts the configuration by
manipulating the LoadBalancer's json_snippet in-place, which is a very bad
policy.

Instead, make a copy of the LoadBalancer resource's template, and use that
that to perform an update.

Change-Id: I0141c3ebc41462f797eb19182a949da0bb4b76a9
Don't manipulate template during abandon

When deleting a stack during an abandon we want to refrain from deleting
the underlying resources, but there is no need to modify their templates to
do so. In fact, that is highly undesirable because it leaves the system in
an incoherent state, and causes problems for moving away from
templates-as-dictionaries to having an internal template API.

Change-Id: Iddbb3c53342da66f0edadb1e7a314c29a3eff75b
Merge "Don't manipulate LoadBalancer template in-place"
Merge "Don't manipulate template during abandon"