Fix svnmerge to run when input is not from a tty.
Fix svnmerge to run when input is not from a tty.

* contrib/client-side/svnmerge/svnmerge.py
  (console_width): Condition on isatty().

Patch by: Simon Brunning <simon@brunningonline.net>
Reviewed by: Dustin J. Mitchell <dustin@zmanda.com>
             Giovanni Bajo <rasky@develer.com>

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion