Fix two dotline bugs for the price of one.

Fix two dotline bugs for the price of one.
1) When answering "No newline at end of file, add one?" with y and
   dot is not at the end of buffer dotline is off by one
2) When displaying the same buffer in two windows, dot in the
   second window is below dot in the first and a newline is entered in
   the first window dotline is not updated in the second.

OK lum