reStructured text has "image" and "figure" . Our CSS styled both of them with a 1px border and a drop shadow effect. I have changed this (in r14100 and r14101) so that this styling only applies to figure, and then we can use image where this kind of emphasis is not appropriate.
I have also added a 10px margin underneath both types of elements, so that the caption gets some breathing room.
Let me know if there are any objections, it's harmless to revert.
-Arne