Remove policy check in db layer for aggregates

Since there already are policy checks in v2 and v3 api layer,
no need to check again at db layer. This patch remove
that check for aggregates. Also added policy test
on api layer for v2 API(v3 already have),
removed 2 test cases in db layer focused admin context.

Change-Id: Ied1fd109be104a9539d1cad7937455852e20ffb2
Implements: blueprint v3-api-policy
Update policy check on each action for certificates

v3 api requested policy check on each action instead of the whole
topic, this patch update the check in certificates and add test cases
for v3 certificates api policy

Change-Id: I9433188beb1e085bc66fc013a285ca2c32fd08f7
Implements: blueprint v3-api-policy
libvirt: Adds missing tests to copy_image

Adds missing tests to the utility method:
  libvirt.utils.copy_image

Change-Id: I1802c26cd5ab9ea0df979cc18e73fb613b87b44e
Add hpet option for time drifting

Since havana, the timezone of windows vm is localtime.
However, there is a time drifting when the windows vm is overloaded.
Disabling hpet option of clock in xml template,
we can sync time without buffering.

From this template,

<clock offset='utc'>
<timer name='pit' tickpolicy='delay'/>
<timer name='rtc' tickpolicy='catchup'/>
</clock>

To this template,

<clock offset='localtime'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>

Implements : blueprint add-no-hpet-option-into-guest-clock
Change-Id: I6441b9d2de5897dd1863b53bd7e2578881b53c67
Delete baremetal image files after deployment.

Unlike libvirt where the image files are needed for running VM's, Nova
baremetal copies them to the remote machine, after which they are no
longer needed. Keeping them sharply reduces the scalability of Nova
baremetal by limiting a single nova-compute to deploy instances whose
disk size sums to it's local disk - but really only needs to be a
concurrency limitation + the kernel/ramdisk files, which are stored
separately.

Change-Id: I7f4791cbd3cff3a0edaccd308c1c47179a4fcf78
Co-Authored-By: Steve Kowalik <steven@wedontsleep.org>
Remove character filtering from V3 API console_output

Removes the character filtering from the V3 API console_output
extension as this was implemented because of a bug in the xml
library where some characters were not escaped correctly. We no
longer need to do this as we no longer support XML.

Partially implements bp remove-v3-xml-api

Change-Id: Id1501143eca17084d4079777a3c6f8c7157fbac7
Merge "Remove character filtering from V3 API console_output"
Merge "Update policy check on each action for certificates"
Merge "Remove policy check in db layer for aggregates"
Merge "Delete baremetal image files after deployment."
Merge "libvirt: Adds missing tests to copy_image"
Merge "Add hpet option for time drifting"