This allows it to participate in Kiway things such as updating
language or common settings.
Fixes: lp:1779558
* https://bugs.launchpad.net/kicad/+bug/1779558
(cherry picked from commit b3f8478)
... and GetMsgPanelInfo.
Step 4 in the g_UserUnit eradication effort.
Also removes a couple of conversion routines that were close
enough to extinction.
(cherry picked from commit c75da51)
* Refresh the view only when changes are made in the caller frame.
* Allows recreate a new instances when try to open the 3D view from a frame taht is not the initial caller
* Remove duplicate code in kicad frames.
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.