tsconfig.json parsing

[hypercross]

seems like tss ignores compiler options in tsconfig.json, and after some digging it looks like typescript parses tsconfig.json into something like {config : /*blah*/, files: [/*blah*/]} and then only the config part is supposed to be sent to ts.parseJsonConfigFileContent. Instead tss sends the whole object.

I'd really like to make a PR for it but I've never used that stuff. So.