New versions of Bind limit the maximum UDP message size to 1232 bytes,
which is the same that newer versions of libunbound propose as maximum via
EDNS in requests, so increasing the limit on the server wouldn't help.
Instead we allow DNS via TCP so the client can switch after receiving the
truncated UDP response.
For documentation purposes the new folders ikev1-algs, ikev2-algs,
ikev1-multi-ca and ikev2-multi-ca have been created. Most of the
test cases have now been converted to the vici interface. The
remaining legacy stroke scenarios yet to be converted have been put
into the ikev2-stroke-bye folder.
For documentation purposes some legacy stroke scenarios will be kept
in the ikev1-stroke, ikev2-stroke and ipv6-stroke folders.