Added a heading "editing page" in page editor for visual appeal; removed use of alternate <?= ?> syntax in installer as it was causing problems on Win2k3 + PHP/FastCGI. (Experimentally using TortoiseHG's hgtk to commit)

<?php

class Text_Wiki_Render_Plain extends Text_Wiki_Render {
    
    function pre()
    {
        return;
    }
    
    function post()
    {
        return;
    }
    
}
?>