some EDNS option names, including DAU, DHU, N3U, and CHAIN,
were not printed in dns_message_pseudosectiontotext() or
_psuedosectiontoyaml(); they were displayed as unknown options.
this has been corrected.
that code was also refactored to use switch instead of if/else,
and to look up the option code names in a table to prevent
inconsistencies between the two formats. one such inconsistency
was corrected: the "TCP-KEEPALIVE" option is now always printed
with a hyphen, instead of being "TCP KEEPALIVE" when not using
YAML. the keepalive system test has been updated to expect this.
EDNS options that print DNS names (i.e., CHAIN and Report-Channel)
now enclose them in quotation marks to ensure YAML correctness.
the auth system test has been updated to expect this when grepping
for Report-Channel options.
e2393ba27b