Update TODO.md
Merge branch 'master' of https://github.com/meisl/lambda into switch_to_lambda_reprs
improve FP-related tests a bit
implement (free? var term) in lambda-style (almost pure)
remove method isNotFree; implement (free-under? var binder term) in lambda-style (almost pure)
implement (free-var name term) in lambda-style (almost pure); reorganize test files
add test helper $contains_ok (for TList s)
add test helper $has_length (for TList s)
fix test comments
add conversion fn convertTList2P6Array, rename convertToListOfPairs -> convertP6Array2TListOfTPairs, move 'em to Conversion/ListADT-conv.pm6
move bool conversion to Bool-conv.pm6; implement free-vars in lambda-style