Fixed some issues with sndrcv kafka tests.
Generating kafka topics dynamically now it kafka tests.
Limited messagecount in some tests to 50000 for now.
Basic features need to be added now.
testbench: Added kafka test with multi kafka instances
All kafka instances are connected to one zookeeper instance.
Diag script has been adjusted to propper start/stop single
kafka instances.
autotools: Added version check for librdkafka to be higher than 0.9.1