* All "Broxygen" usages have been replaced in
code, documentation, filenames, etc.
* Sphinx roles/directives like ":bro:see" are now ":zeek:see"
* The "--broxygen" command-line option is now "--zeexygen"
* origin/topic/vern/content-gap-history:
Refined state machine update placement to (1) properly deal with gaps capped by clean FIN handshakes, and (1) fix failure to detect split routing.
added 'g' $history character for content gaps