The field is populated in this order of preference:
(1) Use a client-identifier option sent by client
(2) Use the server's CHADDR field
(3) Use the client's CHADDR field
Case (3) did not exist before this patch.
* "bro_is_terminating" is now "zeek_is_terminating"
* "bro_version" is now "zeek_version"
The old function names still exist for now, but are deprecated.
* 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"