Bump to sqlalchemy-migrate 0.8.2

This allows us to drop some unsightly sqlalchemy-migrate 0.7.3
patching.

The related requirements change is here:

  Icde6248ca102884323d7912bab0f4a716aa294ec

Change-Id: I5f80dfc07f8256716d025002fc1a1f47e58b2142
Property methods for resource metadata

For OS::Nova::Server which will build its metadata dynamically
based on currently available SoftwareDeployment resources.
This change makes it possible to:
* read and assign resource.metadata as before
* subclassses to override resource.metadata for building dynamically
* allowing access to the simple attribute based resource._metadata
  when necessary

partial blueprint: hot-software-config
Change-Id: Ifd7aa15dd58c96e6b9efafe6b4201a964e140d8d
tests: use server.test not example.com

Change-Id: I1eb2daaf26ea248ebeb2bb147a42902a8cf84755
oslo: delete rpc/securemessage.py

It doesn't exist in oslo anymore.

Change-Id: Iebadc7841e394232e2ecc26908b06dd1a099bb9d
oslo: add py3compat

This is automatically pulled in by the new oslo modules

Change-Id: Idba617fbd6ca889a0322461bff4954cd90c9f32a
Use the new oslo py3kcompat.urlutils

Change-Id: I9e5d00a04460ef54d402b69f781d2a69a3bd0082
oslo: update config generator

Change-Id: I5a456fe8a898bc042e7580386b6602b75fa7e1c0
Merge "tests: use server.test not example.com"
Merge "Bump to sqlalchemy-migrate 0.8.2"
Merge "Property methods for resource metadata"
Merge "oslo: delete rpc/securemessage.py"
Merge "oslo: add py3compat"
Merge "Use the new oslo py3kcompat.urlutils"
Merge "oslo: update config generator"