MFH (r237568, r255422, r255460, r255766, r255767, r255774, r255829,
  r256126, r257954, r261320, r261499, r263691, r263712): upgrade to
  OpenSSH 6.6p1 via 6.3p1, 6.4p1 and 6.5p1.

Differences relative to head:

 - No DNSSEC support since stable/9 does not have LDNS
 - Sandboxing off by default, and uses rlimit instead of Capsicum
 - ED25519 moved to the bottom of the order of preference to avoid
   "new public key" warnings