Simplify ip allocation/recycling to relieve db pressure

I found that multiple calls to delete_port can pile up on the
_recycle_ip operation.  This patch simplifies this operation.  It
reduces the _recycle_ip operation to a single row delete in the ip
allocations table and doesn't touch the availability table.

To acheive the recycling of ips in a pool, this code runs a more
complex operation of rebuilding the availability table when it is
exhausted.  Only one API process will perform this more expensive
operation and others waiting for allocation will immediately benefit.
The amortized cost of this operation is much less than the cumulative
cost of running the more expensive _recycle_ip operation for every
port delete.

IP allocation behaves a bit differently with this patch.  Instead of
giving out the first IP available in a pool, the entire pool will be
allocated before wrapping around and recycling ip addresses that have
been released.  This is a desirable feature as it puts ip addresses in
a sort of quarantine after they are released.  It is easier to
distinguish newly allocated ips from old ones.

Change-Id: Ia55b66128de9986e075b0f87acc401d211cd91d3
Closes-Bug: #1252506
Closes-Bug: #1257815
(cherry picked from commit 89f25623a4345b5044a58cff36e7fd103c6b88e8)
Refactor to remove _recycle_ip

Since _recycle_ip is now just a pass-through to _delete_ip_allocation
it can be removed.

Change-Id: Ifba3da902de599f748038a33ef3bd98ff77c22b9
Closes-Bug: #1269501
(cherry picked from commit 212c755c34c195148c668b553ccd9f371df63420)
Stop removing ip allocations on port delete

The _delete_port() method was manually removing related
IPAllocation instances despite the existence of a perfectly
good cascade deletion relationship in the model.  This patch
puts an end to that nonsense and the potential for deadlock that
it represented.

Closes-bug: #1288379
Related-Bug: #1283522

Change-Id: Ib31550fa9000fc75768a327cb6cc1c419e06568f
(cherry picked from commit 2648aa3561d23e1215e0cc6f446253e5df56c8f6)
Set wsgi logger to use __name__

Although underneath this is the eventlet.wsgi.server server, Other
OpenStack projects, don't use that logger instead they use there own.

This will also mean the wsgi server will stop logging on just the
warning level.  We want wsgi server to at least log on info level
so it will log when a request is processed and what the return code is.

Change-Id: I96fd73b84b4550f85ad96030fea815376901813a
(cherry picked from commit 83ce89f471d887ec9e3aa48c26ffe0d88a1957b1)
Merge "Set wsgi logger to use __name__" into stable/havana
Don't emit log for missing attribute check policy

A missing policy for validating whether an attribute should
be visible or not is a perfectly normal condition, and
there is no value in logging it.

Writing this information to the log is also having a
considerable performance impact on list operations.

Change-Id: Ie9d3ae6b249a5c49f6d81c1e56915174d8479a07
Closes-Bug: 1302467
(cherry picked from commit ef01fb553a141c012c8d8600edd6b709c5807111)
Merge "Don't emit log for missing attribute check policy" into stable/havana
Merge "Simplify ip allocation/recycling to relieve db pressure" into stable/havana
Merge "Refactor to remove _recycle_ip" into stable/havana
Merge "Stop removing ip allocations on port delete" into stable/havana
Merge branch 'stable/havana' of https://github.com/openstack/quantum into havana/stable