Improve HTML+RDFa template

[da2x]

Improvements include:

• structured parable and machine-readable RDFa data (instead of a series of disjointed data fragments) [test by pasting template here]
• clarifies what object is described/licensed (the URL in the about attribute on the root element)
• make better use of Dublin Core properties
• better accessibility, license name set as img[alt] (compression will reduce the long repeated string to virtually nothing)
• the badge image is kept outside the root span element to prevent simplistic implementations from wrongly assuming the license applies to it rather than the resource in the about attribute.
• HTTPS by default (pages load faster as it avoids the redirect and people aren’t exposed to an unencrypted connection)

Suggested updated template (pretty printed here for discussion):

<a href="http://creativecommons.org/licenses/by/4.0/"><img
   alt="Creative Commons Attribution 4.0 International License"
    style="border-width:0"
   src="https://i.creativecommons.org/l/by-nd/4.0/88x31.png" /></a>
<br/>
<span about="https://www.example.com/image.jpeg"
      datatype="dct:Image"
      prefix="cc: http://creativecommons.org/ns# dc: http://purl.org/dc/terms/# dct: http://purl.org/dc/dcmitype/#">
  <span property="dc:RightsStatement">
    <span property="dc:title">Example Document</span>
     by
     <a href="https://www.example.com/about"
        property="cc:attributionName cc:attributionURL dc:rightsHolder">John Human</a>
      is licensed under a
      <a rel="license"
         property="dc:license"
         href="https://creativecommons.org/licenses/by/4.0/">Creative Commons
           Attribution 4.0 International License</a>.
  </span>
</spam>

Current template for reference:

<a rel="license" href="http://creativecommons.org/licenses/by/4.0/">
<img alt="Creative Commons License" style="border-width:0"
     src="https://i.creativecommons.org/l/by-nd/4.0/88x31.png" /></a>
<br />
<span xmlns:dct="http://purl.org/dc/terms/"
      href="http://purl.org/dc/dcmitype/Image"
      property="dct:title"
      rel="dct:type">Example Document</span>
by
<a xmlns:cc="http://creativecommons.org/ns#"
   href="https://www.example.com/about"
   property="cc:attributionName"
   rel="cc:attributionURL">John Human</a>
is licensed under a
<a rel="license"
   href="http://creativecommons.org/licenses/by/4.0/">Creative Commons
     Attribution 4.0 International License</a>.