Fix 'null' response on router-interface-remove operation

To avoid a 'null' response body, the delete operation returns a response
that is consistent with its add counterpart, i.e. we return the router
id with details about the interface being affected by the operation, as
well as the tenant id.

A unit test is added to ensure that the right body is returned and minor
adjustments have been made to the plugins affected by the change.

Long-term, a delete operation should really return 204 w/o a body, but
this requires some major rework of the WSGI handling within Quantum.
This is an interim solution that deals with an 'ugly' response body,
whilst keeping backward compatibility.

Fixes bug 1173284

Change-Id: Icaab87ad0c8561c0690c8f0a14db815d8886bc71
Update RPC code from OSLO

Fixes bug 1172922

Change-Id: Ieb5f58fe3d2c879bc71f4241288e48e35ab54366
Fix port_id filter not honored

Add dict. to map API params to DB columns

Change-Id: I5f10eea77533e91afeb690e39301d7282e1b1620
Fixes: bug #1169706
Avoid initialization of policy engine before extensions are loaded

Bug 1174877

For a particular NVP extension, a database entry was being populated
in the plugin's __init__ method. The entry was added with an admin
context. Grabbing the context caused the policy engine to load before
all the extension were loaded, so rule on extended attribute
were not being parsed correctly.
This cause checks on external networks to fail always.

Change-Id: Icbc759773acab2a7687883d8d2844272c8ea55a3
Set network_device_mtu as integer

Fixes bug 1175060

Change-Id: Ibce28db0575dd6d6f1f998a7b8d6603f3d6dba63
Merge "Fix 'null' response on router-interface-remove operation"
Merge "Fix port_id filter not honored"
Merge "Update RPC code from OSLO"
Allow admin to delete default security groups

Previously there was no way to delete a default security groups which
isn't ideal if you want to clean up after deleting a tenant. This patch
allows default security groups to be deleted by the admin.

Fixes bug 1175393

Change-Id: I2214c7dabf0f2ec960ce10ebbbcdc513bc73664c
Merge "Avoid initialization of policy engine before extensions are loaded"
Merge "Set network_device_mtu as integer"
Merge "Allow admin to delete default security groups"