Advanced rendering options

Hi! I hope I won't bother with too many suggestions.

I noticed the rendering order of the modules is static, because the lower module will always be showed above the higher one, and that is a big limit.

I was thinking to add a Rendering oprion in the Layer menu (or adding a brand new menu), with this features:

Rendering before modules: 1,2,3... . The module where this is set will have higher priority than selected modules on the main list (1,2,3... ), even if it is listed higher.

Rendering behind modules. The same, just the opposite. It will have lower priority even if it's lower on list.

Both should be customized by formulas, in order to have a dynamical rendering order of the modules to be changed even with global variables switches.