Rwalls now resist weak explosions - allowing them to resist aggressive
vines perfectly
Bluespace vines lose their "potential energy" after piercing through a
single tile, so as to not allow station-engulfing monstrosities to grow
unchecked
Vines no longer normally spread on space tiles - this is now reserved for
space covering vines (and bluespace in seldom occasions) only
Makes kudzu events kick off more interestingly