Merge pull request #713 in SNORT/snort3 from analyzerz to master

Merge pull request #713 in SNORT/snort3 from analyzerz to master

Squashed commit of the following:

commit 0ec1cd2494157cd82d01fe8420ab4fc349cd922e
Author: Russ Combs <rucombs@cisco.com>
Date:   Mon Nov 21 14:40:44 2016 -0500

    review updates

commit 5b3912d83b783255fd6089491bdbffc43cbc30d4
Author: Russ Combs <rucombs@cisco.com>
Date:   Sun Nov 20 09:52:33 2016 -0500

    fix analyzer command races

commit d182530ec55a53bd91ddaad01b160dd964c7db06
Author: Russ Combs <rucombs@cisco.com>
Date:   Sun Nov 20 07:44:44 2016 -0500

    unset signal handlers at shutdown

commit 73e31038dbf7e01351810c4f2efb95df642f55f0
Author: Russ Combs <rucombs@cisco.com>
Date:   Fri Nov 18 05:58:18 2016 -0500

    convert to event driven main loop