Fix parrot-feeder and parrot-server shell scripts on Ubuntu

On Ubuntu 13.04, I am unable to run either parrot-feeder.sh or parrot-server.sh.  I believe the problem stems from the usage of the deprecated 'function' keyword.  Removing the deprecated keyword fixed the problem and should make the scripts more portable.  See http://wiki.bash-hackers.org/scripting/obsolete for additional information.