adding templates and use object for outputting DHLM-based client library...

This fixes #194

Here's a sample of what this would look like

  <html data-sly-use.dhlm="${'/apps/acs-commons/sightly/templates/dhlm.html'}">
    <head>
        <style data-sly-call="${dhlm.head @ mode='all'}" data-sly-unwrap></style>
    </head>
    <body>
        <section data-sly-call="${dhlm.body}" data-sly-unwrap></section>
    </body>
  </html>

The mode attribute can be "css" or "js" or "all". "all" is the default.