[css3-multicol] updated editor's draft

The multicol ED has been updated:

  http://dev.w3.org/csswg/css-multicol/

Changes are:

--

Changed "Content in the normal flow" to "Floated or in-flow content", as per:

  http://www.w3.org/TR/css3-multicol/#overflow

--

Revised the pseudo-algorithm, as per;

  http://lists.w3.org/Archives/Public/www-style/2013Apr/0347.html
  http://lists.w3.org/Archives/Public/www-style/2013Apr/att-0225/tmp.html

I've kept:

  - the 'exit' statements
  - these assumptions:

      -- that the block direction is unconstrained
      -- that no column breaks are added through style sheets

I've changed the line numbers. 

--

Revised description of painting order, as per:

  http://www.w3.org/Style/CSS/Tracker/issues/300

This text:

   Column rules are painted just above the background of the multicol element. 

has been changed to:
 
   Column rules are painted in the inline content layer, but below all
   inline content inside the multicol element.

--

-h&kon
              Håkon Wium Lie                          CTO °þe®ª
howcome@opera.com                  http://people.opera.com/howcome