 * Add open-swash Q (#1264).
 * Add ability to customize the width of S-related necks for different kind of letters (#1265).
 * Add Characters
   - NORTH WEST ARROW TO CORNER (`U+21F1`).
   - SOUTH EAST ARROW TO CORNER (`U+21F2`).
   - THREE RIGHTWARDS ARROWS (`U+21F6`).
