An easier way to use ResourceCollection

[auralluring]

Right now ResourceCollection requires you to set a script for the base type. This makes for some UI that is sort of clunky and hard to figure out. (at least for me) But I discovered something recently with EditorResourcePicker. Basically, it has a base_type property which takes a name string of the base type and filters the list down to that class and its inheritors. You might assume this doesn't include custom resources (as is the case for nearly everything else in the engine that uses class names as strings), but it does!

This would allow us to include engine classes as well as an overall more intuitive UI. It would, of course, require the user to register their class, but I think that's a reasonable ask.