Move tests for l3 agent out of L3NatDBTestCase

[Salvatore Orlando]

These class currently has some unit tests like: https://github.com/openstack/neutron/blob/master/neutron/tests/unit/test_l3_plugin.py#L1631

For child classes, like the ones which the execute plugin-specific tests, these are superflous for plugin not running the l3 agent; for plugins running the l3 agent, they are not adding any coverage w.r.t. the unit tests executed against the db module (neutron.db.l3_db).

Pushing them out in a separate TestCase appears to be a sensible, albeit not high-priority, decision.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/43431

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/43431
Committed: http://github.com/openstack/neutron/commit/716af601730402859f101758ac6928b450fa8ac1
Submitter: Jenkins
Branch: master

commit 716af601730402859f101758ac6928b450fa8ac1
Author: Salvatore Orlando <email address hidden>
Date: Fri Aug 23 03:37:57 2013 -0700

    Separate l3 db tests for l3 agent into their own test case

    Bug 1215871

    This patch does a simple refactoring of test_l3_plugin, pushing out tests
    aimed at validating the interactions of the l3 agent with the server.

    These tests explicitly use TestL3NatPlugin, whereas all the
    other tests use a configurable plugin, which might be specificed by a child
    class. This might lead to confusion and possibly errors in unit tests for
    child classes, especially those not using the l3 agent - for which running
    these test is also superfluous.

    Change-Id: Ia9ed320ea775fc548e6a5b711c67c9f3b0ae2f6d