Merge pull request #45 from AlexanderWert/master

changed cobertura version to 2.6
added some unit tests and changed all thread creations to use concurrent
execution of tasks using a threadpool

Change-Id: Ia17cb3c72d9367e7d4f9556b80c03ff038cff117
Signed-off-by: Alexander Wert <alexander.wert@sap.com>