[O] [Bug] Problem with html export of description list items

[Ethan Ligon]

I've just stumbled across what I regard as a bug in the html export of
description list items.

The problem has to do with whether the specification of a description
list includes a trailing space or not; i.e., whether "- Item ::" is
treated the same way as "- Item :: ".  LaTeX export treats these as
identical.  Html export gets confused about what the description list
item is, and winds up generating a "???" for the description.

Here's an example.

#+begin_src org
* Illustration of bug in html export
  - Has a space after the colons :: so will work in latex and html
  - No space after the colons ::so won't work in html
  - Has a terminating space :: 
    - So it works in both html and latex export!
    - Even though it's difficult to distinguish from the next example.
  - Lacks a terminating space ::
    - *Doesn't* work in html export, does in latex.
#+end_src

The relevant bit of the html export
#+begin_src html
  <div id="outline-container-1" class="outline-2">
  <h2 id="sec-1"><span class="section-number-2"></span> Illustration of bug in
html export </h2>
  <div class="outline-text-2" id="text-1">
  
  <dl>
  <dt>This has a space after the colons</dt><dd>so will work
  </dd>
  <dt>???</dt><dd>This doesn't have a space after the colons ::so won't work
  </dd>
  <dt>Has a terminating space</dt><dd>
  <ul>
  <li>So it works in both html and latex export!
  </li>
  <li>Even though it's difficult to distinguish from the next example.
  </li>
  </ul>
  
  </dd>
  <dt>???</dt><dd>Lacks a terminating space ::
  <ul>
  <li><b>Doesn't</b> work in html export, does in latex.
  </li>
  </ul>
  
  </dd>
  </dl>
  
  </div>
  </div>
#+end_src

The relevant bit of the latex export looks like this:

#+begin_src latex
\vspace*{1cm}
\section{Illustration of bug in html export}
\label{sec-1}

\begin{description}
\item[This has a space after the colons] so will work
\item[This doesn't have a space after the colons] so won't work
\item[Has a terminating space] 
\begin{itemize}
\item So it works in both html and latex export!
\item Even though it's difficult to distinguish from the next example.
\end{itemize}
\item[Lacks a terminating space] 
\begin{itemize}
\item \textbf{Doesn't} work in html export, does in latex.
\end{itemize}
\end{description}
#+end_src

Thanks for any help!

-Ethan Ligon