With TexView.markupEnabled the "\n" and "<br />" are rendered at the same time

### Problem description

Setting `markupEnabled` on a `TextView` renders `
` but also treats regular line breaks (`\n`) as new lines. This can be observed in the [bookstore demo](https://github.com/eclipsesource/tabris-js/blob/master/examples/bookstore/AboutPage.js#L7).

#### iOS


#### Windows


### Expected behavior

The `TextView` should only render the
tags and not the line breaks. The following html in the browser yields the expected results:

```html

Authors of book covers:

Paula Rodriguez - 1984
Marc Storrs and Rob Morphy - Na Tropie Nieznanych

Cat Finnie - Stary Czlowiek I Morze

Andrew Brozyna - Hobbit

Viacheslav Vystupov - Wojna Swiatow

Marc Storrs and Rob Morphy - Zegar Pomaranczowy Pracz

Andrew Evan Harner - Ksiega Dzungli`;

```


### Environment

- Tabris.js version: `nightly`
- Device: iPhone SE, Windows 10 Desktop
- OS: iOS 10.3.2, Windows 10

### Code snippet

See bookstore example.
```javascript
const ATTRIBUTION_TEXT =
`Authors of book covers:

Paula Rodriguez - 1984
Marc Storrs and Rob Morphy - Na Tropie Nieznanych

Cat Finnie - Stary Czlowiek I Morze

Andrew Brozyna - Hobbit

Viacheslav Vystupov - Wojna Swiatow

Marc Storrs and Rob Morphy - Zegar Pomaranczowy Pracz

Andrew Evan Harner - Ksiega Dzungli`;
```