Config update

Note that due to some changes to how Mekanism assigns item IDs in the new version, there may be minor damage for users of that mod.
RR 2.6.4.0-EXP XML update

Reimplemented Portal Gun and Gravity Gun for PR reasons.

Implemented Not Enough Keys as well.

This version includes a config for Redstone in Motion due to [REDACTED NOTHING TO SEE HERE], as a courtesy. :)