CSS Overflow Level 3 Planning

This spec should exist to define overflow behavior in more detail and to introduce the overflow-x and overflow-y properties. Issues to address:

• http://lists.w3.org/Archives/Public/www-style/2010Mar/0544.html [overflow, scrollbar clamping, and bidi]
• http://lists.w3.org/Archives/Public/www-style/2009Aug/0006.html and http://lists.w3.org/Archives/Public/www-style/2009Aug/0039.html [define ink overflow vs. layout overflow]
• http://www.w3.org/TR/css3-box/#overflow [overflow-x and overflow-y, turning overflow into a shorthand]
• http://lists.w3.org/Archives/Public/www-style/2010Jul/0513.html [overflow-style: pan]
• overflow-attachment: viewport | local to propagate scrolling/paging control to parent scrolling context?
• Anything else?