Fix memory leak in error path.

OK from miod@
KNF
KNF
More KNF.
More KNF.
More KNF and clean up.
Pull out the sequence number selection and handle this up front. Also, the
correct record is already known, so avoid reassignment.
Switch to the ISC licensed versions of these files, which Google has made
available via boringssl.

ok deraadt@
Specify the correct strength bits for 3DES cipher suites.

From OpenSSL.

ok miod@
Pull the code that builds a DTLS sequence number out into its own function
to avoid duplication. Also use fewer magic numbers.

ok miod@
always compare memcmp against 0, for clarity.
More KNF.
KNF.
KNF.
KNF.
More KNF.
nuke unused test programs; ok jsing
In BIO_get_port(), use strol() with appropriate range checks rather than
an atoi() followed by an unsigned short cast. This stops things like "-1"
and "66536" from being considered to be "valid" port numbers.

ok beck@ deraadt@
Just use SOMAXCONN and IPPROTO_TCP, since we know we have them.
BIO_sock_init() no longer does anything, so stop calling it.