git-gui: Don't linewrap within console windows

git-gui: Don't linewrap within console windows

If we get more than 80 characters of text in a single line odds
are it is output from git-fetch or git-push and its showing a
lot of detail off to the right edge that is not so important to
the average user.  We still want to make sure we show everything
we need, but we can get away with that information being off to
the side with a horizontal scrollbar.

Signed-off-by: Shawn O. Pearce <redacted>