GAL is strict regarding which layers are rendered, therefore to show
ratsnest lines when an item is dragged - the ratsnest layer must be kept
enabled. Ratsnest line visibility is enabled per item and this is the
way to show/hide the lines.
Fixes: lp:1666473
* https://bugs.launchpad.net/kicad/+bug/1666473
Freerouting-specialized menus are removed as FreeRouting is not
maintained or packaged for most OSes. Users can still import/export
SPECCTRA files in KiCad allowing them to interface with a custom
FreeRouting installation.
Includes some dialog changes to go with the menu update.
Includes promoting the Pcbnew graphics mode back to main menu.
Includes renaming Graphics modes to Toolsets.