Define periodic task to sync capsule status

@kevin-zhao, are you working on this, if not can I assign it to myself?

Yes I already submitted a patch. Sorry about that. I forgot to link thepatch with this bug.

Reviewed: https://review.openstack.org/633371
Committed: https://git.openstack.org/cgit/openstack/zun/commit/?id=d0a7940981bb123bfc12d4ed2d24a4bf50e513e4
Submitter: Zuul
Branch: master

commit d0a7940981bb123bfc12d4ed2d24a4bf50e513e4
Author: Hongbin Lu <email address hidden>
Date: Sat Jan 26 23:50:22 2019 +0000

    Consolidate Container and Capsule in compute

    In before, create/delete Capsule has its own RPC api and compute
    manager implementation. The code is largely duplicated with
    the Container equivalent. In fact, the code duplication leads
    to bugs or missing features and it is hard to maintain.

    This commit refactor the compute node implementation for capsule.
    First, the capsule RPC API is removed and the controller will
    use the container RPC for create/delete capsule in compute node.
    Second, the capsule implementation is removed from compute manager.
    Instead, we will reuse the container implementation for capsule.
    Third, we introduce capsule operation in container driver.
    The capsule-specific logic will be implemented by different drivers.

    After this patch, all existing container features (i.e. resource
    tracking and claiming, asynchronized delete, etc.) will be available
    for capsule immediately. In long term, the common implementation
    for capsule and container will be easier to maintain.

    Closes-Bug: #1801649
    Closes-Bug: #1777273
    Partial-Bug: #1762902
    Partial-Bug: #1751193
    Partial-Bug: #1748825
    Change-Id: Ie1d806738fcd945a4f370bdfc7fa8fb5fb815e8d