Add in kvec isodistort tutorial

[Kvieta1990]

This is the tutorial for using the searched k vector in GSAS-II to talk to ISODISTORT and get back the GSAS-II project files for each of the subgroups compatible with the k vector.

I am using a simulated data for writing this tutorial.

[Kvieta1990]

Hi @briantoby As I am working through creating the tutorial, I am encountering some issues. Since I am using the simulated data for the testing and I did the simulation with GSAS-II. So, using the same CIF and instrument parameter file for the simulation and the refinement with the simulated data, I would expect the refinement look nearly perfect. However, it turns out to be not the case. There seems to be a shift between the calculated pattern and the fitted one -- I did not refine anything actually since in this case, we really don't expect anything to be refinable as both the CIF and instrument parameter files are the same between the simulation and the refinement.

Here below I attach my test files. We can discuss about this during our meeting. Thanks!

test_files.zip

[Kvieta1990]

Hi @briantoby Sorry about the delay on this but I just managed to finish up the tutorial for this new capability. Could you please help review and merge the PR? Please feel free to let me know if anything I need to do.

Thank you so much!

[briantoby]

I'm not able to pull this branch locally so I can review it before merging, so I will merge and then review.