RICH EB DST Integration

The event builder (EB) performs 4 main tasks:

1. Read and organize all the detector information from upstream services
2. Associate tracks and detector responses into particle objects
3. Perform a particle identification scheme on those particle objects
4. Export those particles and their associated detector responses to DST banks

RICH integration must happen somewhere between #1 and #3. That requires passing specific data between the RICH and EB packages, and identifying that data is key.

Inputs:

1. Memory-resident EB particles (tracks and associated hits from all (non-RICH) detectors)
2. The RICH::tdc bank
3. Event vertex and start time (?)

Outputs:

1. A PID metric for each particle (and hypothesis?) in REC::Particle
2. The associated responses for the REC::Cherenkov bank (or its future upgrade)