Log request-id for each api call

https://review.openstack.org/331981
Dear bug triager. This bug was created since a commit was marked with DOCIMPACT.
Your project "openstack/python-glanceclient" is set up so that we directly report the documentation bugs against it. If this needs changing, the docimpact-group option needs to be added for the project. You can ask the OpenStack infra team (#openstack-infra on freenode) for help if you need to.

commit 96151efd518021f0e56e6518a1326e6d0ac91981
Author: Abhishek Kekane <email address hidden>
Date: Tue May 17 11:23:28 2016 +0000

    Log request-id for each api call

    Added support to log 'X-Openstack-Request-Id' for each api call.
    If glanceclient is used from command line then following log will
    be logged on console if --debug flag is used.

    DEBUG:glanceclient.common.http:GET call to glance-api for
    http://172.26.88.20:9292/v2/schemas/image used request id
    req-e0c7c97a-8fc0-4ce3-a669-d0b1eb5d7aae

    If python-glanceclient is used in applications (e.g. Nova) then
    following log message will be logged in service logs.

    DEBUG glanceclient.common.http
    [req-be074f1e-1c17-4786-b703-2a221751c8f4 demo demo] GET call to
    glance-api for
    http://172.26.88.20:9292/v1/images/detail?is_public=none&limit=20
    used request id req-9b1dd929-df30-46b2-a8f2-dfd6ffbad3fc

    DocImpact:
    To use this feature user need to set 'default_log_levels' in third
    party application. For example nova uses glance then in nova.conf
    'default_log_levels' should be set as below:

    default_log_levels = glanceclient=DEBUG

    Implements: blueprint log-request-id
    Change-Id: Ib04a07bac41ad2a5e997348f3b0bccc640169dc9