Update Felix configuration guide to include iptable lock file support.
Update Felix configuration guide to include iptable lock file support.

gunjan5/calico,heschlie/calico,bcreane/calico,tomdee/calico,heschlie/calico,gunjan5/calico,tomdee/calico,tomdee/calico,heschlie/calico,caseydavenport/calico,bcreane/calico,heschlie/calico,gunjan5/calico,bcreane/calico,caseydavenport/calico,caseydavenport/calico,heschlie/calico,heschlie/calico,gunjan5/calico,tomdee/calico,gunjan5/calico,gunjan5/calico,bcreane/calico,tomdee/calico,caseydavenport/calico,caseydavenport/calico,bcreane/calico,caseydavenport/calico,bcreane/calico