[hacc] Allow parser-references to refer to partial paths
[ent] Use much-needed partial path backrefs
[vis] Improve/fix model rendering
[vis] Improve skeleton error messages
[hacc] Use std::to_string instead of hand-replacement
[haacc various] Remove most references to std stream library
[hacc] Make C arrays haccable.
[ent] Add look poses in arrays to BipedPoses