ADDED DRC test for solder mask aperture bridging copper from different nets. ADDED visualization of minimum web width processing for solder masks. ADDED allow_soldermask_bridges property for footprints. Fixes https://gitlab.com/kicad/code/kicad/issues/2183 Fixes https://gitlab.com/kicad/code/kicad/issues/1792
Fixes https://gitlab.com/kicad/code/kicad/issues/6821
Also tries to fix a compile issue on gcc.