HTML Visitor do not format links & figure alts

[kasperosterbye]

MicHTMLVisitor asHTMLString: '[this **is** a link](https://somewhere.org)' 

prints <p><a target="_blank" href="https://somewhere.org/">this is a link</a></p>.

Problem is in MicHTMLVisitor>>#visitLink which does not visit the children.

[kasperosterbye]

MicHTMLVisitor asHTMLString: '![this **is** a link](https://somewhere.org)' also returns wrong: <p><figure><img src="/" alt="this **is** a link"><figcaption>this <strong>is</strong> a link</figcaption></img></figure></p>

This is more subtle - but the original source should not be used IMHO

[kasperosterbye]

I'll fix it as part of the inline parser work