e22fa7bbf5
This change adds support for model specific overlays from templates which are rendered at deploy time. The overlay template directory will be searched for a corresponding template (<bundle_name>.j2). If one is found then the overlay will be rendered using environment variables matching AMULET* or ZAZA_TEMPLATE* as a context. The rendered overlay will be used on top of the specified bundle at deploy time. A default overlay is always applied "local-charm-overlay.yaml". This overlay is only used to move the location of the charm being deployed to a relative path so the bundle can use "charm: <charm name>" rather than "charm: ../../../<charm name>"