Fix #147: Add method for stream-line-column
Add a method for stream-line-column
for
fundamental-character-output-stream
that just returns nil.
Since there is a method for stream-start-line-p
and
stream-advance-to-column
for fundamental-character-output-stream
and these methods call stream-line-column
, it makes sense to define
a corresponding method of stream-line-column
.