tsconfig.json parsing using JSON.parse which does not support all features that tsc does

[bbugh]

The TypeScript tsc compiler (and other tools) use jsonc format, that includes comments, but Sucrase uses the built in JSON parser, which has problems:

• JSON.parse does not support comments.
• JSON.parse will fail on trailing commas

This means that the default output of tsc --init immediately breaks this tool.

I recommend using jsonc-parser which is the same package that VSCode uses for reading its json configuration files. This would ensure sucrase supports the same features as TypeScript.