Catch NoResultFound in _get_policy_profile_by_name

Add try-except in _get_policy_profile_by_name to raise
proper PolicyProfileNameNotFound if profile not found in
database.

Also unittest is added.

Closes-bug: #1393399

Change-Id: I3ab50a6870ff77a95e0977c75255e9cbd7286fbb
Eliminate unnecessary indirection in L3 agent

These indirections serve no useful purpose.  Normally, I wouldn't
bother to change them but these make other refactoring efforts a bit
more of a pain.

Change-Id: Ia73c93eb2eaa81d5772b3e0178fdf18f0c275b4c
Fix context.elevated

The current version of elevated method sets for the original context
the admin role too. This change fix this.

Added unittest.

Closes-bug: #1386932

Change-Id: Ife881112efa151e53bfa4b7af35643dcf2d1114f
Imported Translations from Transifex

For more information about this automatic import see:
https://wiki.openstack.org/wiki/Translations/Infrastructure

Change-Id: I754cecc4efba2c9cd385de99901dce8c2188fce0
Test HA router failover

HA failover testing requires the ability for two L3 agents to
co-exist on the same machine. The following changes were made
to support this:

* Add l3 agent ability to simulate nested namespaces by suffixing
  each router namespace with '@host'. For example, if a router
  with id '1' is created, its namespace will be:
  'qrouter-1@host'
* Added test.common submodule which will hold common code which is
  shared between the different kind of tests (unit and funtional).
* Added tests.common.agents submodule which holds test-only agents, and
  added a test L3NAT agent to be used in the HA functional testings.

Co-Authored-By: Assaf Muller <amuller@redhat.com>
Closes-bug: #1374946
Change-Id: I2185fe276d9d32b34c407396e7ed5d6e2801340c
Merge "Test HA router failover"
Merge "Imported Translations from Transifex"
Merge "Fix context.elevated"
Merge "Catch NoResultFound in _get_policy_profile_by_name"
Merge "Eliminate unnecessary indirection in L3 agent"