Includes:
- Fix GAL to draw closed polygons in eeschema
- Add functionality to eeschema to draw arbitary polygons
- Update polygon item previews to have customisable edge colour
- Add new SCH_RULE_AREA class, derived from a poly SCH_SHAPE
- Add SCH_RULE_AREA to paint and plot methods
- Add new rule area color preference to themes
SCH_EDIT_FRAME::SetCurrentSheet( xxx ) was used to switch to a sheet, but
SCH_EDIT_FRAME::SetCurrentSheet() has side effects to the current VIEW
(clear some data used to show the sheet on screen) and does not fully
restore the "old" screen
SCHEMATIC::SetCurrentSheet( xxx ) is now used to switch to a sheet
James J
Jeff Young
Wayne Stambaugh
Marek Roszko
jean-pierre charras