[JS Parser] dot property shorthand for JSX

This is a non-standard backwards-compatible feature that I suspect other tooling will soon adopt (and expect to help other tooling adopt it)

```jsx
var hello = {hi: 'yo'};
export const Foo = () => <Bar {hello.hi} />
```

Desugars into:
```jsx
var hello = {hi: 'yo'};
export const Foo = () => <Bar hi={hello.hi} />
```

This works with defines and macros too.

```jsx
export const Foo = () => <Bar {process.env.NODE_ENV} />
```

```jsx
export const Foo = () => <Bar NODE_ENV="development" />
```