New Waypoint System

[jameslkingsley]

• Waypoint icons are controls almost exactly like entity icons
• PFH is created when units in selection, destroyed when empty
• PFH loops groups in selection
  • Creates the waypoint controls once
  • Adds event handlers
  • Updates icons each frame
• Right-click waypoint control
  • Opens context menu with given waypoint's attached group
  • Implement only context feature for only[] = {Waypoint}; to only show waypoint commands
• [ ] Change waypoint order
• [ ] Delete waypoints
• [ ] Move waypoints
  • Store hovered WP globally
  • Initiate left-drag handler with custom selection type
  • Draw icon for WP movement