reset waypoints by removing unit key instead of adding waypoint entry
store UnitSelection in starting waypoints
try to add a waypoint every time a unit moves between tiles
rename resetWaypoints() and setWaypoint()
add delay when adding waypoints to newly exclusive tiles
I think path can be unambiguous parent even if parent segment would be on different path
implement automatic time travel for non-stacked units (this is so cheeky)
rename simpler moveTo() to moveToDirect()