Provide support for nested objects

With the introduction of the LBaaS v2 API, all objects are capable
of normal CRUD operations. Until now these objects were mostly top-level
constructs, and in then instances where they weren't, they were
manipulated by way of 'actions.'

LBaaS v2, as designed, nests members under pools, and supports all
normal CRUD operations. This means that in order to take action against
a member we need to provide a pool uuid as well as the member uuid. The
python-neutronclient currently does not support this, so this change
makes to possible to do so.

This change adds the capability but does not affect other top-level
object implemenations.

Change-Id: I38c3b78dc077f1f78ebc7e703fe7277a02f53f7a
Partially-implements: blueprint lbaas-api-and-objmodel-improvement
Fix unit tests to succeed on any PYTHONHASHSEED

Many tests rely on order of parameters in URL query, but
queries are constructed from dicts and order of parameters
is non-deterministic. The issue doesn't occur if PYTHONHASHSEED
stays constant, but breaks if random. The fix is needed for
tox>1.7 and Py3.

Closes-Bug: 1348818

Change-Id: I01145df689e90ccd6100fa82092ba3ed222af8fc
Merge "Provide support for nested objects"
Merge "Fix unit tests to succeed on any PYTHONHASHSEED"