log username and tenant like other projects do

[Angus Salkeld]

nova logs look like this:
INFO nova.osapi_compute.wsgi.server [req-c11d2975-c168-486f-96c5-bca19568d995 demo demo] 127.0.0.1 "GET /v2/269b2ee20a8347f49803302663dba398/flavors/detail HTTP/1.1"

heat's have the request-id but not the user tenant

INFO eventlet.wsgi.server [req-5338de68-6de7-4d5c-91ec-a6acf9c8c259 ] 10.0.4.179 - - [24/Mar/2015 02:06:45] "GET /v1/ddc4b8530c024f71a1bfc026c59e6a2b/stacks/AutoScalingSignalTest-776347522-JobServerGroup-spvmmrhuf7u2/5caa9faf-e471-4151-a095-b69a2372bf2e HTTP/1.1"

This is because our context does not return the "user_identity" from to_dict().

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/168220

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/168220
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=04d0e22bf8d7a13434939fc00bcb5c11635addcf
Submitter: Jenkins
Branch: master

commit 04d0e22bf8d7a13434939fc00bcb5c11635addcf
Author: Angus Salkeld <email address hidden>
Date: Fri Mar 27 14:33:23 2015 +1000

    Add user_identity to RequestContext.to_dict()

    This makes heat logging format more consistent with other
    services as oslo.log uses this in the Context formatter:

    https://github.com/openstack/oslo.log/blob/master/oslo_log/formatters.py#L214

    Change-Id: If85fca19d1e37decc35f965b92e6430e46d9842a
    Closes-bug: #1437144