Controller to sync usage data from the Exoscale and Cloudscale metrics APIs to Odoo16

Metrics are collected taking into account product (e.g. object-storage-storage:exoscale), source (e.g. exoscale:namespace), tenant (organization) and date time.

On DBaaS, we also gather information by Plan. That can be seeing in the product. For example, in the case of a PostgreSQL database service, product may look like appcat-exoscale-pg-hobbyist-2.