Add an editor setting to only show 3D collision shape gizmos for selected nodes

[yahkr]

Describe the project you are working on

Any 3d project using collision shapes

Describe the problem or limitation you are having in your project

The scene in the editor becomes messy as more and more collision shapes are added

Describe the feature / enhancement and how it helps to overcome the problem or limitation

A toggle to only show collision shapes on selection of said collision shape

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

Add an editor setting

If this enhancement will not be used often, can it be worked around with a few lines of script?

cannot be worked around easily

Is there a reason why this should be core and not an add-on in the asset library?

This improves the 3d editor.