Workaround for the circular dependency between
`platypush.entities.bluetooth` and `platypush.plugins.bluetooth.model`.
Unentangling the circular dependency would require way too much work,
since the entity model provides several helpers and properties that
depend on the plugin's model.
The workaround in this commit is to simply push those imports down in
the methods that use them, so they won't be imported until those methods
are called, as well as removing some type annotations that depended on
those objects.
Fabio Manganiello
276aff757b
