No Helvetica/sans-serif fonts in Twenty Ten in IE6

[iammattthomas]

nbachiyski pointed me to this -- because of the attribute selector at the end of the Helvetica/sans-serif font declaration in Twenty Ten, IE6 chokes on the entire thing and as such, all text in Twenty Ten in IE6 displays in Georgia.

I'm including a patch that declares the font for submit input elements separately. This is somewhat inelegant, but seems like a reasonable compromise for IE6. Props to nbachiyski for the fix.

[iammattthomas]

Moves font family declaration for inputs with attribute "submit" away from all others, so IE6 correctly displays sans-serif fonts everywhere else.

[nbachiyski]

(In [15532]) Set IE6 incompatible CSS rule in a different selector, because it causes all headings to be set in Georgia instead of Helvetica & co. Fixes #14688. Props iammattthomas

[nacin]

(In [15785]) Set IE6 incompatible CSS rule in a different selector. fixes #14688 for 3.0. props iammattthomas