Removed unused code

Removed unused methods, variables, and arguments
from method signature. Method 'remove_user' was
removed because method 'add_user' is unused and if
we never do add_user then no reason to do remove_user.

Change-Id: I0ef900232bc26b91e9cd192ba29a720ff7de27a3
Remove unnecessary dict copy

The conf object is ignored anyway so there is no point in copying and
updating the object.

Change-Id: I00a0af7433ad49150a3e135a0254030be59b1974
Closes-Bug: #1307781
Sync with oslo-incubator 2fd457b

This syncs Keystone with oslo-incubator commit hash
2fd457bf2ccbeb2b84ffb204778b6417cd5405ba .

In keystone:

 $ rm -r keystone/openstack/common

In oslo-incubator:

 $ python update.py ../keystone

The newer lockutils requires posix_ipc. It's already in
global-requirements.

Keystone uses gettextutils and versionutils from oslo-incubator
so those should be in openstack-common.conf. They were pulled in
as dependencies of other oslo-incubator modules but Keystone
shouldn't rely on that.

Keystone doesn't use log_handler directly so that module was
removed from openstack-common.conf. log_handler is available in
the oslo.messaging library.

Change-Id: I6082f4e0995ca35372f9b061d8f76890aa93250c
Merge "Remove unnecessary dict copy"
Merge "Sync with oslo-incubator 2fd457b"
Merge "Removed unused code"