This commit adds support for UDPLite as specified in RFC 3828
and the corresponding socket options.
It is tested on FreeBSD 10.1 and Linux, the platforms supporting
UDPLite.

Signed-off-by: Michael Tuexen <tuexen@fh-muenster.de>

This patch makes sure that all heaaders start at a four byte
boundary. This is done by not having the ethernet header, which
is 14 bytes long, in the packet buffer.
This fixes the remote mode for platforms having strict alignment
restrictions, like ARM. Without this patch you can't use the remote
mode on a Rasperry Pi running FreeBSD.
This patch has been tested on Linux (Intel) in local and remote mode
and one FreeBSD (Intel and ARM) in local and remote mode.

Signed-off-by: Michael Tuexen <tuexen@fh-muenster.de>

This commit adds support for the CRC32C checksum used by SCTP.
Also add a unit-test for it.

Signed-off-by: Michael Tuexen <tuexen@fh-muenster.de>

Initial commit for the packetdrill network stack testing tool:

  https://code.google.com/p/packetdrill/



Signed-off-by: Neal Cardwell <ncardwell@google.com>