Add qclass to query_t + refactoring

src/utils/common/params.c

src/utils/common/params.h

src/utils/dig/dig_exec.c

src/utils/dig/dig_main.c

src/utils/dig/dig_params.c

src/utils/dig/dig_params.h

src/utils/host/host_main.c

src/utils/host/host_params.c