Remove Net resource id attribute

This patch removes the 'id' attribute of Net resource to encourage Ref
usage, and fixes some attribute description.

Partial-Bug: #1230228
Change-Id: I1674e67f6c20007ef809db8e16a707922e5cda1c
Remove Neutron load balancer resources id attributes

This patch removes id attributes from Pool and HealthMonitor as people
should use Ref instead.

Partial-Bug: #1230228
Change-Id: I92d74fcaa2a5443cb38bc647056d4fc7a95677a0
Merge "Remove Net resource id attribute"
Merge "Remove Neutron load balancer resources id attributes"