Event listening is only activated if specified in the instrumentation
description.

Change-Id: Ib070020e9c1d454c0a30dcb44e6a486c86a325a2
Signed-off-by: Henning Schulz <henning.schulz@sap.com>
Merge pull request #32 from Henning-Schulz/master

Event listening is only activated if specified in the instrumentation description.