and shortly after I removed the code that limited drawing of very short links... niantic chance the server and start returning them again!
so probably better with this re-enabled
helper function for plugins to create new hooks
plugin: draw tools: register plugin-specific hook, and call when drawn items are added/edited/deleted, and also when imported and cleared
plugin cross_links: change reliance on Leaflet.Draw internals, instead use the new draw-tools hook for monitoring add/edit/delete/import
also fixes cross_links not updating after an import/clear