Support for mobile URL Schemes "tel:" and "sms:"

Hi,

in my opinion it should be possible for vulcanize to detect `tel:` and `sms:` URL Schemes as well beside the current `data:` and `mailto:` Schemes.
```html
<a href="tel:+49123123456">Make a call</a>
<a href="sms:1-123-123456">Write SMS</a>
```