Now that we have improved wrapping to support DTWW, it would be nice  
if the fringe could mark visual lines that end with a newline.
Currently, we can only mark continuations, but given that  
continuations are rather common, and lines with a newline at the end  
more rare (marking the end of paragraphs), I would much prefer to mark  
the exceptional lines.

This would provide analogous functionality to longlines-show-hard- 
newlines in longlines-mode.