Add log translation hints for Heat

Current oslo libraries support translating log messages using different
translation domains and oslo would like to see hints in all of our code
by the end of juno. So Heat should handle the changes out over the
release.

blueprint log-translation-hints

Change-Id: If0fba45f970ef0618b0bf3fdc46eaa2dc7fac0d0
Merge "Add log translation hints for Heat"