Currently the API allows an operator to delete a flavor even when it
is in use by a load balancer. This patch corrects this by blocking
the deletion of a flavor that is currently in use by a load balancer.
It also correctly handles load balancers in the "DELETED"
In order to support Python 3.7, pylint has to be updated to 2.0.0
minimum. Newer versions of Pylint enforce additional checkers which can
be addressed with some code refactoring rather than silently ignoring
them in pylintrc; except useless-object-inheritance which is required to
be silented so that we stay compatible with Python 2.x.
This patch adds support for flavor metadata validation by the amphora driver
and support for setting the load balancer topology via a flavor.
It also adds "flavor_id" to the load balancer table in the database.
This patch adds flavor and flavor_profile tables.
It also implements flavors and flavorprofiles apis.
Partially-Implements: Blueprint octavia-lbaas-flavors
Co-Authored-By: Michael Johnson <email@example.com>