Dev netmap v2.0

Here's a pull request for the netmap code.  I spent part of the day getting this all into the 2.0dev branch.  I've had it laying around for a while.  I also did some testing with the newest version of netmap posted on the Internet.  This still needs a lot more testing of various configuration and runmode combinations.

Most testing was using:

suricata -c /usr/local/etc/suricata/suricata.yaml --netmap=eth2 --runmode=workers

Also, testing was done using netmap on Linux, not FreeBSD.

Please code review.