Updated openstack/openstack
Project: openstack/heat  6ca66128f1906eaf730900a6a934d29414325bca

Reduce Server update complexity to below 20

One of the goals to polish Heat code is to make sure the complexity is
below 20.  This patch refactors the Server resource implementation
regarding its update logic so that it meets this requirement.

This is a pure code refacto patch, so no test cases are modified.

Change-Id: I18c6ada4386c0a091ae1d369db91c6a3d6429f34