This enables arbitrary DNS lookups (with the caveat that RRDATAs are
currently not deserialised into a record-type-specific format).
An error condition has been defined for error-responses from the HTTP
server which provides interactive restarts for attempting a new call
with different parameters.
Adds a package definition file and moves the current client into
client.lisp
Note that the client is not working at all at this commit as this is a
work-in-progress snapshot.