CrossManager update

[datafelix]

CrossManager can now read glTF and has other new formats available.

[javagl]

There's a small JSON formatting error, at "FBX', "glTF 2.0" there is a ' instead of ". In doubt, I can fix this locally later, but it may be simpler to fix it so that this PR can be merged directly

[datafelix]

There's a small JSON formatting error, at "FBX', "glTF 2.0" there is a ' instead of ". In doubt, I can fix this locally later, but it may be simpler to fix it so that this PR can be merged directly

Woops, sorry. It is now fixed.