Reimplement client utility to support named parameters instead of positional

[efirs]

Named parameters alllows more flexible usage of utility, for example:
./st_client add -d db1 -t t1 -c c1 -s svc1 -i mysql -o kafka -f avro -v 1
instead of fixed positional parameters:
./stcli add svc1 t1 db1 clst1 mysql kafka avro 1 "{}"