* Adds the ability for multiple borers in the same host. Adds upgrade paths for chest and leg borers.
* Fully implements the ability to have multiple borers in a single body, complete with unique chems, verbs, and genetic unlocks.
* Fixes to do with movement_speed_modifier, and some conflict resolution.
* Fixes some paths.
* Fixes conflicts.
* Fixes more conflicts.
* Inorganic limbs can no longer be infested. Removes arm borers' ability to produce creatine.
* Removes all mention of the term "cortical" from borers.