Provide single header to include for all collection types
Downstream analysis codes now require
#include "eicd/InclusiveKinematicsCollection.h"
#include "eicd/ReconstructedParticleCollection.h"
while it may be easier and more transparent for users to use a single overall header
#include "eicd.h"
or mabye
#include "eicd/DataModel.h"