bugs, missing features and spec violation

[ghost]

@icefapper

1. Import and Export is broken. Does not handle early errors. E.g

   var a, b; export default a; export { b as default };
export { a, b as c }
export default 1; export default 2;
export { a as default }
export { a }

All this fails. See also #12

2. Async parses for ES6
3. Exponent parses for ES6
4. ESTree violation. Author call it "extra information".

And does not handle

({a({e: a.b}){}})
(function* ({e: a.b}) {})
(function ({e: a.b}) {})

And most of the todos in the code haven't been fixed for months