In a new microversion (1.22) expose support for processing
forbidden traits in GET /resource_providers and GET
/allocation_candidates. A forbidden trait is expressed as
part of the required parameter with a "!" prefix:
required=CUSTOM_FAST,!CUSTOM_SLOW
This change uses db and query processing code adjustments
already present in the code but guarded by a flag. If the
currently requested microversion matches 1.22 or beyond
that flag is True, otherwise False.
Reno, api-ref update and api history update are included.
Because this microversion changes the value of an existing
parameter it was unclear how to best express that in the
api-ref. In this case existing parameter references were
annotated.
Partially implements blueprint placement-forbidden-traits
Change-Id: I43e92bc5f97db7a2b09e64c6cb953c07d0561e63
4e07d81260