Update openstack/common/periodic_task

The following commits are in this update:

1771a77 Adjust import order according to PEP8 imports rule
4bfb7a2 Apply six for metaclass
0ea069e Removed calls to locals()
1a2df89 Enable H302 hacking check

Change-Id: I5d15d9772002a2f764acef16e28bcfa16a9760c0
Initialize iptables rules on initialization of MetadataManager

To avoid multiple initialization of iptables rules if there are a few
workers for metadata service, perform iptables configuration in
__init__() of MetadataManager.

Change-Id: I674c04f973318f06cbb98693f0a884c824af8748
Closes-Bug: #1097999
Setting the xen vm device id on vm record

Currently, while setting the device_id, the hypervisor
version is being incorrectly handled since the method
get_major_minor_version expects either an int, float,
or string format. However, the xen hypervisor
version is stored in the session product_version as a tuple.
This fix correctly uses the version to set the appropriate
device_id on the vm record. Also, removing the method
get_major_minor_version as it is not needed anymore.

Closes-bug: #1260178

Change-Id: I6b1353cdb7cc856b34f02e3d3679c142ba032533
Change default ephemeral FS to ext4.

The ext3 filesystem does orders of magnitude more I/O than ext4 in
mkfs - a brief benchmark showed 14m to make a 1TB ext3 filesystem
vs 7 seconds to make a 1TB ext4 filesystem, with the ext3 filesystem
doing upwards of 6GB I/O.

Since ext4 has been a default in all major Linux distributions for
a long time now - RHEL5 has it as default, for instance - there is
no reason to default to ext3: users that need ext3 can configure
that themselves.

DocImpact

Change-Id: I833356af81df743a63d4442d389be82bc25f3914
pass the empty body into the controller

This allows POST and PUT reqeusts without content-body. The
default body: None will be passed into the controller, and
will be validated in the controller, so it fixes the bug 1253089.

When the request method is GET or DELETE, the content-type
and body in the request will be ignored
.
When POST or PUT a request with body but without content-type,
it will return "unsupported the content-type provided" with
response code 400.

side-effect: The method which handle the request method: POST
or PUT must have the parameter: body. Otherwise, it will raise:
"got an unexpected keyword argument 'body'"

And some tests are updated due to this change.
The parameter: body are also added for some actions which are
mapped to the method: POST or PUT.

Closes-bug: 1253089

Change-Id: Icda59feed439625bbbe079444feeda57576ef131
Merge "Update openstack/common/periodic_task"
Merge "pass the empty body into the controller"
Merge "Setting the xen vm device id on vm record"
Merge "Initialize iptables rules on initialization of MetadataManager"
Merge "Change default ephemeral FS to ext4."