Improved support for <![CDATA[...]]>

As requested: improved support for CDATA to address newlines and escape issues.

Three CDATA variants are included:

 1. `cdata` for the standard `<![CDATA[ ... ]]>` wrapper 
 1. `cdata-js` that is suitable for inclusion into a JavaScript `<script>` tag: `//<![CDATA[\n ... \n//]]>`
 1. `cdata-css` that is suitable for inclusion into a CSS `<style>` tag: `/*<![CDATA[*/\n ... \n/*]]>*/`

All variations come with the standard escape sequence for `]]>` text.