ProtectEditing should modify cursor style on disabled elements

[madeleineostoja]

Right now it's unintuitive that certain things on the page don't work when you click them, it's hard to put 2 and 2 together that 'oh it's because I'm in edit mode with Simpla'. The pointer events disabler should either a) also toggle the cursor to not-allowed, or b) toggle opacity. Opacity would be much harder because it's a cumulative effect for each tree, and it can seriously mess with site design.

Ideally it could also add a title, saying that it's disabled in edit mode and to use cmd+e to toggle in and out.