Allow NoMoreFloatingIps to bubble up to FaultWrapper
Allow NoMoreFloatingIps to bubble up to FaultWrapper

Fixes LP 1026167.

The fix for LP 1021721 caught the wrong exception in order to
address floating IP quota over-run. NoMoreFloatingIps is raised
when the floating range is exhausted, whereas FloatingIpLimitExceeded
is raised on over-quota.

Also the HTTPRequestEntityTooLarge exception raised is mapped
to 500 Server Error due to the required retry-after header being
left unset.

We now allow the NoMoreFloatingIps to bubble up to the FaultWrapper
middleware, where its mapped to a 404 status due to it extending
the NotFound exception.

Change-Id: Id35c487113059ec3053f2f9e9e7eca24854ac02c

citrix-openstack-build/oslo.versionedobjects,openstack/oslo.versionedobjects