[FEAT] Kill All Zombies talisman added to SuperLemmix

[WillLem]

The previously redacted Kill All Zombies talisman has been reinstated, so SuperLemmix now has this feature! It will require some testing and possibly further development due to the issues namida raised in the linked topic, but from what I can see so far it work a treat and is potentially a lot of fun!

I've also added support for this Talisman to the Editor, so when the next version of SuperLemmix is released we can get creating zombie-killing levels straightaway

In the meantime, please do read the linked topic and then let me know here in this topic if you have any suggestions or comments relating to this feature.