Removing handling of Ctrl+c

[gr211]

Why

Specific handling of ctrl+c signal was counter productive on heavily loaded streams.

I used a boolean to exit the loop faster, but it was still pausing for a few seconds. A bigger overhaul would have been to pass that boolean to all shard consumers as well (ie not just the sink).

A possible alternative could be the usage of priority queues (to handle Termination signal faster).

But all in all, it now appears a counter productive handling in the sense a typical unix command would immediately exit with code 130. There is no valid reason to make kinesis-tailr behave any differently.