Provide a getter for map config that accesses the OL map state

[silvester-pari]

Instead of relying on the config property of eox-map, a getter for the current state of the map could be useful, that directly checks things as vanilla OL layers, view settings etc.

[silvester-pari]

This turns out to be not possible with the current setup, as we don't have information over the layer/source types. One would have to import all layer/source types, and then loop through all layers, and check if it's an instance of any of the imported layers/sources etc.