This directory contains a partial clone of The Lobster Programming Language (https://github.com/aardappel/lobster), the scripting language being used in TreeSheets. See that repo for any documentation on building/using it.
Because that repo dwarfs TreeSheets in size, and we only need a small part of it, the clone is kept up to date with a simple script (reclone.bat/.sh) instead of git submodule/subtree etc.