Comment 8 for bug 353370

So relying on tty detection is not really an option as the rest of bzrlib really want a width to either
fill or truncate the output lines.
While truncated lines are not a problem with large width values, filled ones are.

Until we address the various usages of terminal_width(), I'll just revert the proposed patch.

As a poor workaround, if you set the COLUMNS environment variable if will take precedence over the 80 default value
used by bzrlib.