Remove HPD specific RICH code
Big cleanup of the RICH codebase, removing code specific to HPDs.
This MR is a cleaning out a lot of now obsolete code, as a first step towards a future MR that will add support for a realistic PMT encoding and decoding.
There will be a number of updates in other LHCb projects to adapt.
Lbcom!486 (merged) Rec!2126 (merged) Boole!286 (merged) Panoptes!112 (merged) Moore!551 (merged) Brunel!1038 (merged)
Edited by Christopher Rob Jones