[JUNIT] updated PowerMock-EasyMock libraries

Change-Id: Icb4d57ea1f4aa6d2fa4155c13fb664f1c779faf6
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/923
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>