Skin templates for the standard (non-CMF) skin.

Warning - don't edit filterissuesdtml, issuetrackerdtml,
recentchangesdtml, searchwikidtml, useroptionsdtml here, they are
auto-generated. Edit the master copies in content/dtml instead.

Why are we still using DTML in here ? These forms originated as
DTML-scripted wiki pages and it's easier to evolve them that way.  So we
are still using that code, wrapped in a page template for consistent
handling.

