COPY request is broken

[Akihito Takai]

COPY request is broken because COPY middleware is created in swift.
<<https://github.com/openstack/swift/commit/46d61a4dcd9a5d9157625c06d6fe7d916e80c3d2>>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/347225

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/347225
Committed: https://git.openstack.org/cgit/openstack/storlets/commit/?id=4819eddad8475f1fd0de34ea036f1e84d1f28527
Submitter: Jenkins
Branch: master

commit 4819eddad8475f1fd0de34ea036f1e84d1f28527
Author: Akihito Takai <email address hidden>
Date: Tue Jul 26 19:06:38 2016 +0900

    Fix COPY request

    Currently COPY middleware is created in swift, and
    "COPY" is allocated to the left of the "storlets_handler"
    in the pipeline of proxy-server.
    Therefore COPY request is processed in the COPY middleware.

    In this case , there is the following problem.
    1. Failed content_length check
     Because storlets doesn't set content_length.
    2. COPY request handles storlets twice
     storlets is processed in the GET request and the PUT request.

    This patch moves storlet_handler to the left of
    copy middleware, to process COPY request in storlet_handler,
    as we did with previous swift.

    Change-Id: I325e28451bf0ee1dead88e0cb6009d3f7265b677
    Closes-Bug: #1606446