Stop accidentally closing standard error.

I had carefully set up a 'canclose' override flag which allowed
umlwrap to override the normal process of closing its fds to generate
EOF in the case where the fd was the one it was using for its own
standard error - but I only checked that flag during the main loop of
umlwrap, and not in the startup loop that closes pointless duplicate
fds. The latter was closing standard error.


git-svn-id: svn://svn.tartarus.org/sgt@10227 cda61777-01e9-0310-a592-d414129be87e