remove visit_t structure. Some memset usage fix

src/include/66/service.h

src/include/66/utils.h

src/lib66/exec/ssexec_disable.c

src/lib66/exec/ssexec_enable.c

src/lib66/exec/ssexec_init.c

src/lib66/exec/ssexec_reconfigure.c

src/lib66/exec/ssexec_remove.c

src/lib66/exec/ssexec_resolve.c

src/lib66/exec/ssexec_signal.c

src/lib66/exec/ssexec_start.c

src/lib66/exec/ssexec_status.c

src/lib66/exec/ssexec_stop.c

src/lib66/exec/ssexec_tree_admin.c

src/lib66/exec/ssexec_tree_resolve.c

src/lib66/exec/ssexec_tree_signal.c

src/lib66/exec/ssexec_tree_status.c

src/lib66/instance/instance_create.c

src/lib66/module/regex_replace.c

src/lib66/parse/parse_rename_interdependences.c

src/lib66/sanitize/sanitize_init.c