Sentek Runic Teleporters

Added a whole bunch of new config options and mechanical fixes:

• Configs for distance are now a pair of lists, meaning you can add new blocks with new distance values. You want grass to count for 69 blocks? Grass can count for 69 blocks. You want to remove stone from the list of blocks? You can do that.
• Option to stop bedrock from being replaced by air if the air-pocket option is on. Stops people from using air-pockets to open holes they shouldn't.
• Option to stop people from accidentally teleporting out the bottom of the world. Instead, shunts them up until they arrive at layer 1, so they probably drown in bedrock anyways, but that's life.
• Mechanically, now calculates destinations on separate maps for each time a core is activated. Previously, if two people activated cores at the same time, only one would go anywhere. This is no longer a problem.