Support jsonc in json.decode

[ashi009]

JSON is great for hosting raw data, but not great for human-written configs. It would be nice that json module could allow jsonc inputs (eg. with comments and trailing commas).

[stepancheg]

This repository is about starlark spec, not specific implementation of starlark.

Starlark spec does not define json module (although it probably should).

So this issue should be posted against specific implementation you are using (I guess, Bazel?)

[ashi009]

For bazel indeed. Will create one for them instead.