Fix object_compat decorator for non-kwargs

This makes the object_compat decorator gracefully handle the case
where a manager method gets executed with a non-kwarg instance.

Related to blueprint compute-api-objects

Change-Id: I274c4f854b4c15b936bed3301e97bccbe33a44dc
Make db/api strip timezones for datetimes

Before objects, we always used TZ-naive dateteimes, but actually
in the UTC timezone. With objects, we use TZ-aware datetimes with
UTC as the zone. This makes the DB api strip out the timezone
before passing them to sqlalchemy, which expects naive ones.

Related to blueprint compute-api-objects

Change-Id: Id28378c6c68cabcc677bf8cf7b47a4446c397505
Fix default argument values on get_all_by_filters()

This was passing incorrect default arguments to the actual db api
method.

Related to blueprint compute-api-objects

Change-Id: I8e9db96a0d3b0124b9f9431de91e8037a10abac7
Make notifications properly string-convert instance datetimes

Instance objects use real datetimes for launched_at and terminated_at.
This patch makes the notification information function properly
handle those.

Related to blueprint compute-api-objects

Change-Id: I8622662a83ff0bdc75ffc9e267c5485925326f24
Merge "Fix object_compat decorator for non-kwargs"
Merge "Make db/api strip timezones for datetimes"
Merge "Fix default argument values on get_all_by_filters()"
Merge "Make notifications properly string-convert instance datetimes"
Merge remote-tracking branch 'm_src_repo/citrix-fixes' into build-temp