Add the first basic pktgen samples script pktgen_sample01_simple.sh,
which demonstrates the a simple use of the helper functions.
Removing pktgen.conf-1-1 as that example should be covered now.
The naming scheme pktgen_sampleNN, where NN is a number, should encourage
reading the samples in a specific order.
Script cause pktgen sending with a single thread and single interface,
and introduce flow variation via random UDP source port.
Usage example and help:
./pktgen_sample01_simple.sh -i eth4 -m 00:1B:21:3C:9D:F8 -d 192.168.8.2