Use stdlib logging

I guess this loses us automatic logging of details from request context.

Change-Id: I7413f025231c14b7cbdc9e90099407bc6c7943e1
Remove use of openstack.common.local

This means we no longer set the request context for the current thread
so that it can be used in logging.

We do need to add this back later, but it might be in the form of a
get_current_context() method.

Change-Id: I3f08a85e2019affddec829e2ea008b5c10707660
Remove use of gettextutils

We don't have any infrastructure for localizations in oslo.messaging
so using this is pointless right now. I'm also generally not convinced
we want to translate any of the strings in this library anyway.

For now, just add a dummy _() function. We can can unmark the strings
later.

Change-Id: I1b6a698ee5558c50dc5eafee1f5f05ee2570435e