Log Message:
Update to 3.1.1
By default, no longer try to use libnet.  You must now specify --enable-libnet (#148)
Remove support for pcap_snapshot_override which was never added to libpcap (#140)
Rewrite L2/DLT code in tcpedit/tcprewrite to be plugin based (#82)
tcpprep & tcprewrite no longer require root access (#3)
Remove libnids dependancy for flowreplay

And many more, see the following for all the details:

http://tcpreplay.synfin.net/trac/browser/trunk/docs/CHANGELOG?rev=1886