procedure: http-current-date ->
procedure: http-date->string a ->
sph-time-date-object -> string
procedure: http-parse-date str ->
procedure: http-parse-date->time a ->
string -> integer:seconds/false
syntax: http-status-line code
procedure: http-uri-query-alist->string a ->
procedure: http-uri-query-string->alist a [separator] ->
assumes that uri is valid
procedure: http-utc->date a ->
integer:utc-nanoseconds-since-unix-epoch -> string
procedure: http-write-date date port ->
procedure: http-write-status-line code port ->