generic_command wouldnt run
./subnettools truc
in case  there's another command starting with truc
PARTIAL FIX

Signed-off-by: Etienne Basset <etienne.basset@ensta.org>
cleanly FIX the matching command issue
but will not print more than 39 matching commands in case of ambiguous command
Late, going to BEDDDD

Signed-off-by: Etienne Basset <etienne.basset@ensta.org>