check_nfs_io: Added new project
check_nfs_io: Added check_nfs_io.pl
check_nfs_io: Fixed warning and critical value description
check_nfs_io: Set path to nfsiostat
check_nfs_io: changed perfdata output
check_nfs_io: 
Added -t for type warning/critical
Fixed worng parsing of nfsiostat
check_nfs_io: Status code "OK" if no type is given