Fix report step number associated with substeps.

It appears summary files by convention expect all substep data points to
be chunked together with the data point at the end of the report step.

opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp

@@ -344,7 +344,8 @@ namespace Opm
                     eclIO_->overwriteInitialOIP(simProps);
                 }
                 // ... insert "extra" data (KR, VISC, ...)
-                eclIO_->writeTimeStep(timer.reportStepNum(),
+                const int reportStepForOutput = substep ? timer.reportStepNum() + 1 : timer.reportStepNum();
+                eclIO_->writeTimeStep(reportStepForOutput,
                                       substep,
                                       timer.simulationTimeElapsed(),
                                       simProps,