Merge pull request #88 in SNORT/snort3 from crc/gtp to master

Merge pull request #88 in SNORT/snort3 from crc/gtp to master

Squashed commit of the following:

commit 4e987387e53ddc84f807df00aafcbb73d3dd8b92
Author: Russ Combs <rucombs@cisco.com>
Date:   Tue Oct 20 12:00:50 2015 -0400

    fix multi gtp encap alert

commit 1f718dcb84f461740493f4df586909813469ff17
Author: Russ Combs <rucombs@cisco.com>
Date:   Tue Oct 20 11:24:35 2015 -0400

    update bug list

commit e29dfb142dbf645f3c7f30891ff0032417035848
Author: Russ Combs <rucombs@cisco.com>
Date:   Tue Oct 20 06:48:18 2015 -0400

    test fixes and readability changes

commit 9f976d3f8d74ac5b3fa0700c424f4397c78c5385
Author: Russ Combs <rucombs@cisco.com>
Date:   Fri Oct 16 07:53:21 2015 -0400

    initial port of gtp preprocessor