Textile justified or centered header not parsed

In textile we can center à header with 

```
h1=. Test
```

 that should produce the following HTML

```
<h1 style="text-align:center">Test</h1>
```

but markup.rocks transpile it to 

```
<p>h1=. Test</p>
```

In a similar way we can justify (`h1<>.`) and right align (`h1>.`).
