Show map in /locations and /asset/[id]/locations

I opened a pull request that does the first part of this: https://github.com/farmOS/farmOS/pull/779

This PR takes the first, simplest, and most impactful step towards [Issue #2551091: Show map in /locations and /asset/[id]/locations]( https://www.drupal.org/project/farm/issues/2551091 → ).

It adds a map of locations to the /locations page in farmOS.

It does NOT add a map of locations to the /asset/[id]/locations pages. This has additional complexity, and I don't think there's a lot of value in taking this first step, and tackling the second part in a follow-up.

This PR also makes another general change, which is to rename/replace the current dashboard map type a locations map type (and also cleans up some dependencies). The thought behind this change is that the current dashboard map type is not dashboard-specific at all (other than the fact that it's only used on the dashboard). It is provided by the farm_ui_map module, not the farm_ui_dashboar` module, and it adds layers for all locations to the map. So this just generalizes that to be more reusable, and then uses it in the /location page.

If we merge that, then I think we can rename this issue to focus on the next step of adding maps to /asset/[id]/locations pages.

If we merge that, then I think we can rename this issue to focus on the next step of adding maps to /asset/[id]/locations pages.

I took a quick look at what will be needed for this. The main complexity is that we generate the geometry layers in our farm_asset_geojson View. We will need to be able to contextually filter those Views based on a parent asset ID. This is not currently possible with current Views handlers (that I'm aware of). I think we will need to code our own custom contextual filter for it.

Once we have that contextual filter in place, we can add an option to our asset_type_layers behavior that allows it to pass a parent asset ID into the Views contextual filter. Then we can use that new option in LocationHierarchyForm and it should "just work"!