Ant's chainsaw massacre :P

Ugh. Old SMF 2.0.x markup. :P
This one started getting over the top, so I thought I should get it in now.
Have started on the stuff mentioned in https://github.com/elkarte/Elkarte/issues/624
Not completely done yet. Lots more crud to kill.
Other deprecated things (not mentioned in #624) are flow_auto class on dl.settings
(the .settings dl's already have overflow auto; in the css, so not needed in markup)
and the old .hrcolor class (just use plain hr everywhere)
and width="100%" or style="width: 100%;" on the table_grid class (again, set in css anyway).
Most of those should be gone now.
There are also some tweaks to markup and presentation for the search, and search memberlist, pages.
A bit of other minor tarting up too, but nothing radical. Hey ho.
Signed-off-by:Antechinus <darthechidna@bigpond.com>