VESUVIO: Use different IP files for diffraction

### Technical specifics

Technical specifics

What: Use different a IP files for diffraction (the diffspec file) and all other algorithm runs, add a new transformation for the vesuvio transformations.
Why: Requested by a user
Who (will benefit) : Users of the Vesuvio
How (are we doing this now): Copying how the IP file is currently handled.
Technical caveats: None