fix bug with ViDlrDfa.next: we previously did not consider the case of cursor starts on a line containing nothing but a blank \n newline. We consider this now, returning the same index when it occurs.

fcore/cursor-dfa/vi-dlr-dfa.sml

@@ -30,7 +30,15 @@ struct
                 val isFinal = isFinal
               end)
 
-         val fStart = Folder.foldNext
+         fun fStart (idx, absIdx, str, tl, currentState, counter) =
+           if String.sub (str, idx) = #"\n" then
+             if counter = 1 then
+               absIdx
+             else
+               Folder.foldNext
+                 (idx + 1, absIdx + 1, str, tl, currentState, counter - 1)
+           else
+             Folder.foldNext (idx, absIdx, str, tl, currentState, counter)
        end)
 
   structure ViDlrForDelete =