Outlining spans for jsx elements

From https://.com/Microsoft/vscode/issues/47454











**TypeScript Version:**  2.9.0-dev.20180409


**Search Terms:** 
- getOutliningSpans
- fold / folding
- jsx

**Code**
For the jsx:

```js
const a = <div
    about="bla"
    accessKey="bla"
    autoCorrect="bla"/> 
```

**Current Behavior**
No outlining spans returned 

**Request**
Return outlining spans for multline jsx tags

Other cases:

```js
const a = (
    <div>
        a
    </div>
)
```

Description