Huawei driver did not change REST-URL automaticlly

[zhaohua]

Huawei driver now support multi REST-URLs, which means user can write more than one REST-URLs in the config file(seperated by ";"), and driver can choose the usable one to set up a connection(see function "login" in rest_client.py
of huawei driver).

But if the choosed REST-URL have some failures, huawei driver can not change to another REST-URL automaticlly.

To resolve this, rewrite the "call" function in rest_client.py of huawei driver. If REST command failed to send, driver will do a "login" process to set up another connection, and send the failed command to a new REST-URL again.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/214500
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=6e827667ef732ed48e78fcc8cb867067169ea6f9
Submitter: Jenkins
Branch: master

commit 6e827667ef732ed48e78fcc8cb867067169ea6f9
Author: zhaohua <email address hidden>
Date: Wed Aug 19 15:57:48 2015 +0800

    Huawei: fix multi REST-URLs bug

    Huawei driver now supports multi REST-URLs, which means users can
    write more than one REST-URLs in the config file(seperated by ";")
    and driver can choose the usable one to set up a connection(see
    function "login" in rest_client.py of Huawei driver).

    But if the chosen REST-URL has some failures, Huawei driver can
    not change to another REST-URL automatically.

    To resolve this, rewrite the "call" function in rest_client.py of
    Huawei driver. If REST command failed to send, driver will do a
    "login" process to set up another connection, and send the failed
    command to a new REST-URL again.

    And change REST command timeout to 52s, change login timeout to 4s,
    to avoid long time waiting for failure.

    Change-Id: I50701b19896941db2a57984bd26a06ab7d2a7b4b
    Closes-Bug: #1486326