Port guides, notes, etc. away from QQuickPaintedItem

[mitchcurtis]

Where possible, we should paint via Qt Quick primitives to improve rendering performance.

• Guides.
• Notes.
• Rulers? Might be too much work.
• TileGrid.
• SelectionItem?
• RectangularCursor? Probably not inefficient enough to make a difference.
• SelectionCursorGuide.