Use the blockquote and cite tags in the quote block template for the html5 backend

[GoogleCodeExporter]

I'd like to request for the HTML blockquote and cite tags in the quote block 
template for the html5 backend.

Currently, the quote block is rendered entirely using HTML div elements. The 
current approach lacks the proper semantics for a quote block and it renders as 
a regular paragraph without the AsciiDoc stylesheet.

By switching to blockquote and cite tags, it makes rendering in places that 
don't have a AsciiDoc-specific stylesheet look reasonable, in addition to it 
being more semantically correct.

I propose the following template in the quote block for the html5 backend:

[quoteblock]
<div class="quoteblock{role? {role}}{unbreakable-option? unbreakable}"{id? 
id="{id}"}>
<div class="title">{title}</div>
<blockquote>
|
</blockquote>
<div class="attribution">
<cite>{citetitle}</cite>{attribution?<br>}
&#8212; {attribution}
</div></div>

This change requires two minor additions to the AsciiDoc stylesheet:

cite {
  color: navy;
}

blockquote {
  padding: 0;
  margin: 0;
}

Original issue reported on code.google.com by dan.j.allen on 26 Jan 2013 at 8:52

[GoogleCodeExporter]

It's worth noting the two most notable front-end frameworks, Bootstrap and 
Foundation, both use the blockquote and cite tags in this way. Bootstrap 
differs slightly in that it uses the small tag to wrap the attribution, but 
there is heavy debate over what the right tag is for that purpose, so I say 
let's just change the obvious ones.

Original comment by dan.j.allen on 26 Jan 2013 at 9:09