These are passed through unchanged to the html img tag. If you include a
`caption` parameter, the caption will be displayed centered beneath the image.
-Note that for the `align` parameter to work, you have to make sure that the
-`img` directive isn't surrounded with newlines, as the [[Markdown]] renderer
-would otherwise put the image into its own paragraph, inhibiting this
-functionality from working. On the other hand, CSS should probably rather be
-used instead.
-
The `link` parameter is used to control whether the scaled image links
to the full size version. By default it does; set "link=somepage" to link
to another page instead, or "link=no" to disable the link, or