[INTERNAL] changed IProgressMonitor in OPN

The class now uses the DPP IProgressMonitor interface.

Change-Id: I961a6f1b944ed6ad4f958aa11772166cd73f887a
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1806
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>