virt/firewall: NoopFirewallDriver::instance_filter_exists must return True

Otherwise, virt.libvirt.connection.ensure_filtering_rules_for_instance()
results in infinite loop.
And eliminate NullFirewallDriver as it's same to NoopFirewallDriver.
This patch fixes bug 953781.

Change-Id: I7936b3c69e9269041defd1ef7e5dda2de1f96dab
Sort results from describe_instances in EC2 API.

Fix bug 827619.

This bug pointed out that EC2 sorts the results of of describe_instances
by the launch time.  Make our implementation of the EC2 API behave the same
way.  Previously, instances coming out of the db API were sorted by the
key we wanted, but in the opposite order.  You can now specify both a
sort key and order.  The behavior is the same by default, but the EC2
API sets the parameter to do an ascending sort.

Change-Id: Ifd0bc79ad4c4c8c45809dbb1ac2dadf8abcfd4c3
Merge "Removes default use of obsolete ec2 authorizor."
Merge "Sort results from describe_instances in EC2 API."
Refactor glance id<->internal id conversion for s3

 * Moves nova.image.s3.S3ImageService functions for converting
   between glance ('image_uuid') and internal (db) ids to ec2utils:

       get_image_id => ec2utils.glance_id_to_id
       get_image_uuid => ec2utils.id_to_glance_id

 * Refactors ec2utils.glance_id_to_id to create a new S3Image
   object associating a glance id to an internal id if such a
   mapping does not already exist.  Previously, only calls to
   nova.api.ec2.cloud.CloudController.describe_images would
   add new mappings, but now any attempt to convert a glance id
   to an internal id will succeed, resolving bug 948286.

 * Adds 2 convenience methods to ec2utils, as per bcwaldon:

       ec2_id_to_glance_id
       glance_id_to_ec2_id

 * Since this is a strict refactor and only streamlines existing
   well-tested functionality, this change includes no new tests.

Change-Id: I810afe05223228df1bcc20a0ac688d8c62c472b4
Make fixed_ip_disassociate_all_by_timeout work.

Fix an issue in the SQL api where fixed_ip_disassociate_all_by_timeout
was getting an array of tuples instead of IDs from a model_query.

This should resolves issues where fixed IPs don't get dissassociated
via the network managers periodic task.

Fixes LP Bug #953708.

Change-Id: Iac485cdcda072ee248237e6c4a31113685f5b980
Remove date_dhcp_on_disassociate comment and docs.

Remove date_dhcp_on_disassociate comments/docs.
This option no longer exists.

Change-Id: Ia1462abf6166a4a7c53fba7fe231dc13a542480d
Map image ids to ec2 ids in metadata service

* Fixes bug 953319

Change-Id: I96c1a7f260833adc40b0b07d38bccba4a233e091
Merge "Hack to fixup absolute pybasedir in nova.conf.sample"
Changes remove_fixed_ip to pass the instance host

 * fixes bug 953379

Change-Id: I9c507b68af04d51d5d248b0c52f34646a46bd882
Merge "refactoring code, check connection in Listener. refer to Bug #943031"
Use a FixedIp subquery to find networks by host

* Fixes LP954341
* The FK removals missed this FK reference. Updated function to use
    a subquery in the filter

Change-Id: Ia61d6536deb78e1aa16c5a94956bf919aa3356ba
Merge "add convert_unicode to sqlalchemy connection arguments"
Merge "Use a FixedIp subquery to find networks by host"
Merge "Remove date_dhcp_on_disassociate comment and docs."
Merge "Map image ids to ec2 ids in metadata service"
Fix backing file cp/resize race condition.

 * Fixes bug 953831

Change-Id: I39950b16c9b76159b16203f7b8b504cae5475516
fix bug 954488

Docstring update

Change-Id: Ic0c60818a7097e777927f3801dd674ce72571224
Merge "Fix backing file cp/resize race condition."
Cleanup flags

sql_max_retries: removed (unused)
instance_usage_audit_period: fixed help
default_schedule_zone: fixed help

Change-Id: I952b38497987780d30622fef526edd2d53860f99