[css-text-4] Option for 'true' alignment with text-align

http://dev.w3.org/csswg/css-align/#overflow-values describes the
concepts of 'safe' and 'true' alignment.

The 'text-align' property defaults to 'safe' alignment.  I think it
would be useful to add an option for 'true' alignment.
Syntactically, I think this could be done by adding an optional
'true' keyword that could come before or after the current value
space of the 'text-align' property.  I think this would be a useful
addition to css-text-4.

The use case I heard was that it would be particularly useful when
combined with 'text-overflow: ellipsis', when showing data where the
end is more important than the start.  For example, a constrained
space showing a phone number, where the end of the number might be
considered more important to show than the start, could be aligned
as 'text-align: true right; text-overflow: ellipsis' so that any
overflowing phone numbers would have the start of the number
overflowing (e.g., "0016177616200" being shown as "...7616200").

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
             Before I built a wall I'd ask to know
             What I was walling in or walling out,
             And to whom I was like to give offense.
               - Robert Frost, Mending Wall (1914)