Bind proper DockerManager implementation on boot.
Removed superfluous log statement.
Added updated dockerfile.
Added updated dockerfile.
Removed superfluous log statement.
Delete staging directory when BuildRunner finishes.
Reverted last commit.
Add test packaging phase to pom.xml
Improved stop and remove procedure as well as cancelling jobs.
Merged master into docker-improvements branch.
Merge pull request #6 from devhub-tud/docker-improvements

Improved stop and remove procedure as well as cancelling jobs.
Merged master into killing-and-timeouts branch
Merged master into killing-and-timeouts branch