[O] two simple derived backend questions

[Matt Price]

Hi folks,

I apologize fro relying on your charity for htis question -- I ought to figure this out myself, but am so slow that I've run out of time.

I dhave a number of lecture slides writen in org-mode. Normally I simply export to reveal.js using org-reveal. However, I now have to share these notes with a co-instructor who uses markdown, but not org.  This is not fatal; I can export to markdown mode and use pandoc to create the reveal.js slideshows. 

However, there are two small difficulties:

a) add a horizontal rule

pandoc expects a horizontal rule at each slide division.  So, if possible, I would like to add an hhr element at the end of every headline. 

b) speker notes

More importantly, org-reveal allows the use of speaker notes, thus:

#+BEGIN_NOTES

whatever I put here

#+ END_NOTES

is exported as:

<aside class="speaker-notes">

whaever I put here

</aside>

However, these blocks are ignored by the markdown exporter. 

Presumably I need to add a filter, or build a very simple derived backend, but my attempts thus far haven't been very successful.  I would really appreciate some suggestions! Thank you,

matt