TeX support done. Code is on http://test.wikipedia.org/

Changes since last version posted to wikitech-l: * texvc judges HTML to be either conservative (renders on most browsers, likely to look good) or liberal (renders on recent Mozilla and probably on other new browsers, should be readable, but no warrancy about how will it look like) * boolean math_conservative column added to math table * There are 4 options in preferences: * Always PNG * Conservative HTML or else PNG (default) * Any HTML or else PNG * Leave as Pseudo-TeX (for text browsers mostly) Thanks to this <math> can be used for both inline (which will usually end as HTML) and displayed (which will usually end as PNG) math. * HTML does italics right, and correctly supports \mathit and \mathrm * Support for other formating options removed in HTML (but maybe \mathbb wouldn't be such a bad idea) * Font size changed from 140 to 120.

Criterium of conservativeness is using nothing more than: * ASCII * greek literals * subscripts, superscripts * \mathit (also \it \textit) * \mathrm (also \rm \textrm) * \mbox (also \hbox \vbox)

Todo: * add "math" => 1 to default preferences in all language files (done for En and It only now). * add math_conservative column and the rest of math table to default db creation script and add some db upgrade script which adds math table.

Please test it.