The WordPositionComparator is optionally called by text extraction algorithms
to help insure words found in a line are ordered using the x coordinates
of the bounding box in the cartesian plane's fourth quadrant. The sorting
tries to order the word blocks via the coordinate system rather then the order
that they were plotted in and thus shouldn't effect LTR or RTL writing formats.
It's assumed that all WordText that is a child of LineText will not be
sorted on the y access. The class LinePositionComparator will be used
to insure that lines are ordered correctly in the parent PageText array.