bug#20411: 24.3; Docstring of `next-single-property-change'

[Eli Barzilay]

The documentation for `next-single-property-change' has:

  Return nil if the property is constant all the way to the end of
  object.  If the value is non-nil, it is a position greater than
  position, never equal.

Both of these are wrong when a bound is given.

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!