Creates a link to a diff of a [WikiPage].

Why would you use this instead of a standard anchor?  The LinkToTag automatically adds things like the correct class information (for styles), the jspwiki.baseURL property, etc.

----

!Usage

<wiki:DiffLink page="<page name>" format="anchor|url" version="<version number>" newVersion="<version number>">
;:''Link text''
</wiki:DiffLink>

!Parameters

;__page__: Page name to link to. If not set, uses the current page.
;__format__: If "anchor", creates the full hyperlink (<a href="...">link text</a>); if "url", outputs only the URL.
;__version__: The older version of the page.  Can be "latest" to refer to the latest version; or "current" to refer to the current version; or "previous" to link to the previous version.
;__newVersion__: The newer version of the page.  Can be "latest" to refer to the latest version; or "current" to refer to the current version; or "previous" to link to the previous version.

!Example
{{{
<i>
This page was last changed on 
<wiki:DiffLink version="latest" newVersion="previous">
    <wiki:PageDate/>
</wiki:DiffLink> 
by <wiki:Author />.
</i>
}}}

Displays a text similar to the bottom of this page.