Update log message to support translations

Add i18n support to a missing message

Change-Id: Ie4b2c32fbcc03266a1bfc08796b2dc6eebdc7edb
Add "body=" argument to v3 API unit tests

This patch adds "body=" argument to v3 API unit tests for avoiding
the test failures due to KeyError when applying the API validation
framework to "create a server" API.

_process_stack() of nova's wsgi passes kwargs which includes 'body'
like:
    {'body': {u'server': {u'name': u'my-server', [..]}}}
to an API method. The validation framework finds a body with the
keyword 'body' from the kwargs, and validates the body with the API
schema. So this changes is also for fitting the arguments to the wsgi
behavior.

Partially implements blueprint nova-api-validation-fw

Change-Id: Id5fa416e021b529e20aca3701e3f159bb316e7fb
Merge "Add "body=" argument to v3 API unit tests"
Merge "Update log message to support translations"
libvirt: support configurable wipe methods for LVM backed instances

Provide configurable methods to clear these volumes.
The new 'volume_clear' and 'volume_clear_size' options
are the same as currently supported by cinder.

* nova/virt/libvirt/imagebackend.py: Define the new options.
* nova/virt/libvirt/utils.py (clear_logical_volume): Support the
new options. Refactor the existing dd method out to
_zero_logic_volume().
* nova/tests/virt/libvirt/test_libvirt_utils.py: Add missing test cases
for the existing clear_logical_volume code, and for the new code
supporting the new clearing methods.
* etc/nova/nova.conf.sample: Add the 2 new config descriptions
to the [libvirt] section.

Change-Id: I5551197f9ec89ae2f9b051696bccdeb1af2c031f
Closes-Bug: #889299