minor, support logging to file or stderr (via `-') via -l|--log

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, refactory mon_beef_cb(), ...

put peek bits into mon_beef_peek(),
put activity bits into mon_beef_actvty()

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, make a quick exit from mon_beef_actvty() if last activity/report times don't work out

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, provide getter ud_socket_addr() for dst network

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, use ud_socket_addr() to determine network address assoc'd with a ud_sock_t

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, also log the beginning and the end of monitoring a network

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
hygiene, kick ev_async watcher and let ev watchers live in main's stack

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, check magic values when hdr.ini != UD_PROTO_INI to ease transition

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, bring back QMETA and ute tick decoding again (and only tentatively)

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'tool/unsermon' into next

* tool/unsermon:
  minor, bring back QMETA and ute tick decoding again (and only tentatively)
  minor, check magic values when hdr.ini != UD_PROTO_INI to ease transition
  hygiene, kick ev_async watcher and let ev watchers live in main's stack
  minor, also log the beginning and the end of monitoring a network
  minor, use ud_socket_addr() to determine network address assoc'd with a ud_sock_t
  minor, provide getter ud_socket_addr() for dst network
  minor, make a quick exit from mon_beef_actvty() if last activity/report times don't work out
  minor, refactory mon_beef_cb(), ...
  minor, support logging to file or stderr (via `-') via -l|--log