Also fixes a bug where a FOOTPRINT_EDIT_FRAME was being passed
in to a PCB_EDIT_FRAME.
Also tidies up Modedit settings handling for settings which can't
be edited in Modedit's preferences dialog. They're now copied
from Pcbnew.
Fixes: lp:1768477
* https://bugs.launchpad.net/kicad/+bug/1768477
fp viewer uses the default colors, because it has no color setup dialog.
class_colors_design_settings: remove not used members.
Fix issue in modedit: the color config was never read.
- support for background color setting
- removed several global config settings (such as g_Drc_On)
- wrapped most of global config settings in PCB_GENERAL_SETTINGS class
- reorganized PCB general options dialog to clearly mark which options concern only the legacy canvas
- new GAL feature for legacy users: double-click (or E) to change track width available as an option.
Fixes: lp:1530543
* https://bugs.launchpad.net/kicad/+bug/1530543
Fixes: lp:1707145
* https://bugs.launchpad.net/kicad/+bug/1707145