Show highlights for "Orders" geometries

[IanMayo]

We're not rendering orders yet. We will do, in #1889

Once we are - then when the player selects the "Orders" in "My Orders" or "Adjudication" - then we should highlight the geometries that represent that orders object.

Here is a library that may help: https://github.com/FacilMap/Leaflet.HighlightableLayers

[IanMayo]

No. The orders are just too dense.

We will not show orders by default. We will only show orders if they are marked as selected.