Set the default_log_levels to include keystoneclient

This creates a loggger for keystoneclient so we don't get:
"
No handlers could be found for logger "keystoneclient.middleware.auth_token"
"

bug 1152584
Signed-off-by: Angus Salkeld <asalkeld@redhat.com>

Change-Id: I72d4de37799956b33371826aae50d8ac1ee333b1
remove unused dependencies

* tools/pip-requires: Remove lockfile and netaddr.
* doc/requirements.txt: Likewise.

Change-Id: Id1dd406bd998ca6516364ee8f068222464781084
Switch to python-keystoneclient 0.2.3.

Fixed the bug #1151665 by having python-keystoneclient dependency to
version >=0.2.3.

Also fixed the issue of setting the fake memory cache for keystone
middleware in unit test by using the correct configuration and request
environment.

Change-Id: Id3706bea6083c03adc46a8716c5cb8074339fc45
Merge "Set the default_log_levels to include keystoneclient"
Merge "remove unused dependencies"
enable xml error message response

return xml error message when Accept:application/xml request received.
default to json response when none specified.

Change-Id: Idd454c5bc76adb583bc0a9afce9f31659e7fe2ac