Merge pull request #1040 in SNORT/snort3 from expose-u2_packet to master

Merge pull request #1040 in SNORT/snort3 from expose-u2_packet to master

Squashed commit of the following:

commit 2439da6fc82c8876a4fe846b19a673689fc905d2
Author: Victor Roemer (viroemer) <viroemer@cisco.com>
Date:   Mon Oct 16 13:26:24 2017 +0000

    cleanup

commit 6f8aa06a3e92190ba72613f0b61a31371322484a
Author: Victor Roemer (viroemer) <viroemer@cisco.com>
Date:   Fri Oct 13 09:23:14 2017 -0400

    Move u2_packet.cc

commit c30de3bca9f2f70dcdc43e10b8a0324976b2b16c
Author: Victor Roemer (viroemer) <viroemer@cisco.com>
Date:   Wed Oct 11 10:17:13 2017 -0400

    build: remove u2_packet.h from loggers/Makefile.am

commit 504f0e68d6d929e0991bf1a16d03347d247237fa
Author: Victor Roemer (viroemer) <viroemer@cisco.com>
Date:   Wed Oct 11 08:28:39 2017 -0400

    log: Make U2PseudoHeader a public interface