I23: Discuss with scientists + analysis for kappa + omega interactions

There may be some kappa angles where omega 0, 90 does not work. We should discuss how to solve this.

* Can we restrict doing the centring at only some kappas
* Does it matter if centring is done at a different kappa to data collection
* Can we do the 3d xray centre calculations with not entirely orthogonal grids
* Will we need to add other omegas into the motion program/XRC code

Start by discussing the four kappa/omega questions with the scientists, then inspect the motion program and XRC code mentioned in the issue. Done means an agreed approach for centring restrictions, differing collection kappas, non-orthogonal 3D X-ray centre grids, and any additional omega requirements.

Written by the indexing model from the issue text.