mediawiki.jqueryMsg: Refactor handling of replacements/parameters in links
You should now be able to use replacements/parameters (such as '$1')
anywhere inside both link text and link target, in both external links
('[http://foo/ Bar]') and wikilinks ('[[Foo|Bar]]').
As a side effect of various cleanups, HTML in link text is now preserved
in all cases and is never wrapped in <span class="mediaWiki_htmlEmitter">.
Added test cases for it all.