[css-text-decor-3] Replace text-underline-position by something more generic

I hope it's not already too late for this, but as I already pointed out
earlier several times[1][2][3] I'd like to see text-underline-position not
to be part of the spec. Instead there should be a more general way to
define the position of text decorations.
text-underline-position - as its name implies - is restricted to
underlines. It disregards overlines and blocks future enhancements to the
spec regarding arbitrary text decorations.

Sebastian

[1] http://lists.w3.org/Archives/Public/www-style/2012Aug/0651.html
[2] http://lists.w3.org/Archives/Public/www-style/2012Sep/0462.html
[3] http://lists.w3.org/Archives/Public/www-style/2012Oct/0484.html