small changes to pier-blog, pier-math

[Damien Pollet]

Two detail changes…
- I made pier-math generate transparent PNGs (imperfectly but that's
dvipng not doing what its man page says)
- individual blog posts are now wrapped in the same <div class="post">
as in the blog view… but I suspect this design intentional, for the
RSS feed… ?

PS. NetNewsWire gets Doru's feed but not the one from my local image.
Vienna seems to accept both, but an online validator wasn't too happy
with the feed…

-- 
Damien Pollet
type less, do more [ | ] http://typo.cdlm.fasmz.org