Copy more formats

Not sure if this would be possible without an upstream request, but if we consider allowing copying of other content types, we can also copy a pre-formatted friendly looking anchor link rather than just the raw html.

```
<h1 id="foo">Lessons about foo</h1> < copier here > 
```

=>

```
<a href="blahblahblah#foo">Lessons about foo</a>
```