Improvements to RICH pixel background algorithm
Implements some bug fixes to the background algorithm, and adapts to the changes in LHCb!2036 (merged).
Relatively large diffs in the PID performance in the QM tests are expected. A reoptimisation of the tuning of this algorithm is planned, that might gain some performance. Longer term a completely new algorithm more specific for PMTs is also forseen.
This MR also updates the example RICH options, adding a number of new files for the 'new' PMT data.
Edited by Marco Cattaneo