Fix hyperlink rendering in package description

The previous code rendered the contents of the hyperlink to a string of
HTML before embedding it into the anchor element, which caused inner
HTML elements to appear escaped in the final document. Embedding the
contents directly without rendering them results in no escaping.

Author: rhendric

src/Distribution/Server/Pages/Package/HaddockHtml.hs

@@ -27,7 +27,7 @@ htmlMarkup modResolv = Markup {
   markupOrderedList   = ordList . map snd,
   markupDefList       = defList,
   markupCodeBlock     = pre,
-  markupHyperlink     = \(Hyperlink url mLabel) -> anchor ! [href url] << maybe url showHtmlFragment mLabel,
+  markupHyperlink     = \(Hyperlink url mLabel) -> anchor ! [href url] << fromMaybe (toHtml url) mLabel,
   markupAName         = \aname -> namedAnchor aname << toHtml "",
   markupPic           = \(Picture uri mtitle) -> image ! (src uri : maybe [] (return . title) mtitle),
   markupMathInline    = \mathjax -> toHtml ("\\(" ++ mathjax ++ "\\)"),