[CSS] Deferring rtl/ltr annotations to L4

Dear i18nwg,
   I'm writing to inform you that the CSSWG resolved to defer the ltr/rtl annotations
to level 4. This is because Kenny raised some design-level issues that we want to
address, and taking them to CR now would preclude that.
   http://lists.w3.org/Archives/Public/www-style/2012Mar/0243.html
   http://lists.w3.org/Archives/Public/www-style/2012Mar/0397.html
We know these features are important for bidi, but we want to get them right.
That's all! Expect to see them in a CSS4 Draft Near You very soon. :) It might
take awhile yet to figure out a good solution to the problems Kenny raises,
though!

~fantasai