Issue Redirect Stdout in cli-filter

We need to make sure only our stdout gets written to stdout. Right now GnuPG prints to stdout when a key is not found. Possible solutions:

• redirect with dup/dup2 http://www.eskimo.com/~scs/c-faq.com/stdio/rd.kirby.c
• redirect with fcntl http://www.opengroup.org/onlinepubs/009695399/functions/fcntl.html
• patch gpgme's posix-io.c to do the redirect