Deletion of Layers : deletion in the current Q4TS geopackage

The current Q4TS geopackage should be updated when a layer is deleted:

• user delete a layer in the Layer's browser : QGIS ask for delete confirmation
• Q4TS plugin check if the layer is associated to the current Q4TS geopackage : in this case Q4TS ask for delete from geopackage confirmation