farmhosts - displays hosts and their static and dynamic resources
    Displays information about hosts. It also lists all the job id which running on that node. The state of farm node is displayed in 5 bits, FJDOB.
           1st bit is F if the node is free for more job, otherwise is "-"
           2nd bit is J if the maximum jobs are running on the node, otherwise is "-"
           3rd bit is D if the node is down, otherwise is "-"
           4th bit is O if the node is offline, otherwise is "-"
           5th bit is B if the node is busy but no job running, otherwise is "-"
     Most time, node status only contains one bit, for example: F---- Free (running jobs are less than max job) -J--- Job-Exclusive (maximum jobs are running) --D-- Node or pbs mom is down ---O- Offline (set to offline for service) ----B Busy (high cpu but no job running which indicate previous job exit abnormally) Sometime, the status of a node can has more than two bits. If a node is set to offline before the jobs finish, the status will be -J-O-. If server lost connection to a node when pbs mom die, the status will be -JD---.
         Print the command usage on standard output and exit.
     -s state
         Show the host status only have specified state state: free (F), Job-Exclusive (J), Down (D) Offline(O), Busy(B)
     -c cluster_id
         Show the host status in specified cluster (not used in this version)