fix #3665

AllowStartPosition now receives the ready-state of
each player as an argument too, making its complete
signature as of 95.0:

  AllowStartPosition(
    number clampedPos.x, number clampedPos.y, number clampedPos.z,
    number playerID,
    number readyState,
    number rawPickPos.x, number rawPickPos.y, number rawPickPos.z
  )

where readyState can be one of:
	PLAYER_RDYSTATE_UPDATED = 0 -- player picked a position
	PLAYER_RDYSTATE_READIED = 1 -- player clicked ready
	PLAYER_RDYSTATE_FORCED  = 2 -- game was force-started (player did not click ready)