Migrate Vates/Inelastic_Workflow to new API

re #7703
Migrate Inelastic/CommonFunctions to new api

re #7703
Migrate SliceViewerPythonInterfaceTest.py to new API

re #7703
Migrate MDEvents/scripts/mdevents_optimize.py to new api

re #7703
Migrate speed_vs_numevents.py to new api

re #7703
Migrate NormaliseToUnitTest.py to new api

re #7703
Migrate NormaliseToUnitTest.py to new api

re #7703
Merge branch 'feature/7703_new_api' into develop