Proposal: Packages section in the project Settings

At the moment we have various import buttons: "Import Area Lights", "Import Ammo", "Import Basis". We also don't have an easy way to include Draco and MeshOptimizer. All of these import some files to the project that the people really don't need to see there.

I think we should create a new section in settings, perhaps called Packages, and list all these there with a tickbox. This would include a default engine supported version of the package into the build.

In place of all these "Import .." buttons, we'd have button such as "Enable this feature here", that would bring you to the Packages settings.

Each line in packages could look like:

[ ] Ammo Physics v 1.2.3 (255kb)
[ ] Area Lights v1.0 (100kb)

The user can include the version that is tested to be compatible with the engine easily. If they want different version, they would untick this and import it the usual way.

Ideally the list (json) of supported packages would be part of the engine, and released with the engine. So that if in the engine we update to newer Draco module, we'd update the json file, and when people use this version of the engine in the Editor, it would automatically start using new module. Or let user upgrade?

The issue names no files or tests. Start by tracing the existing Import Area Lights, Import Ammo, and Import Basis controls and the project Settings UI. Before implementation, settle the package manifest, version, and upgrade behavior; done would require an agreed design for listing, enabling, and redirecting users to Packages settings.