Makes a number of changes to the proposed resource-providers blueprint
database schema:
- Adds resource_providers.generation field along with lengthy
explanation as to the necessity of this field in compare-and-update
claim logic
- Adds resource_providers.name field to be used with
generic-resource-pools feature
- Adds can_host field to help in future scheduler work
Change-Id: Id875d46222d65f84df8b87a629005f326d15c26b
blueprint: resource-providers