Merging HTT Simulation (Trigger/TrigHTT) into athena/master

With the slow move away from Rel 21.9, this is a first request to merge HTT simulation into athena/master. HTT is of course a project that no longer exists, but the HTT simulation infrastructure will still be extremely useful for the EF Tracking team over the next ~1 year and perhaps longer. That is because all the Hough Transform simulation and linear chi^2 fitting code is in the HTTSim framework, among other things. We have, however, tried to clean up all the HTT-specific pieces of code (those that explicitly references superstrips or associative memory).

We have purposely left this package name in place so that it's clear where this framework came from. We considered renaming things as EF Tracking or something similar to that but that can easily give the wrong impression.

The packages are quite extensive, and we fully acknowledge they will need a fair bit of help getting put into place. So this will not be a short-term MR, but we thought best to get started. As of now, HTTsimulation does run in athena/master, and we can get sensible output. We haven't fully tested the wrapper production (the first input stage for the simulation) as the old machinery to run our algorithms does not work with CA. That is a work in progress but shouldn't affect all the other work that remains to be done here.

The set of packages are the work of a collaborative effort of many people, but for this MR I think @tbold, @fpastore and @jmasik are sufficient to help