Reference image IAL

[snan]

In the following kramdown example, writing alt text via the IAL works for the inline image but not for the referenced image:

Here is an inline ![smiley](smiley.png){:height="36px" width="36px" alt="Marshall McLuhan"}.

And here is a referenced ![smile]

[smile]: smile.png
{: height="36px" width="36px" alt="Marshall McLuhan"}