[css2] Although the edits look big, they are mostly editorial. Rewrote sections, however, on calculation of width and height of abs. positioned boxes. Please review anyway since it should be all a little clearer.

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extra : convert_revision : svn%3A73dc7c4b-06e6-40f3-b4f7-9ed1dbc14bfc/trunk%401389

Author: ianbjacobs