Makes all 32-bits of all physics, rendering, and navigation layers available in editor.

[rune-scape]

Resolves godotengine/godot-proposals#2770
Please let me know if I missed anything.

[qarmin]

Can you make a print screen how it looks in editor?

[EricEzaM]

Appears to just be a 4x8 grid.

There was some good discussion about the UX of various grid sizes and implementations in that proposal, not sure why you would jump straight into a PR, rather than discussing there first.

[YuriSizov]

Even more discussion on RC too. This doesn't implement one of the described features: latter sections need to be collapsible, we don't want to waste vertical space on showing a bunch of squares most people won't need.

[rune-scape]

My bad, I had the code lying around and I failed to read the contributing guidelines. What should happen to this PR?

[EricEzaM]

Once some sort of conclusion is reached in the proposals discussion thread, you can update this PR if that is something you want to do. Otherwise, you can close it if you don't have interest in updating it or would prefer someone else to implement the changes.

[dalexeev]

Please close this as the proposal was implemented in #51039 and #51040.

[akien-mga]

Superseded by #51039. Thanks for the contribution nonetheless!