Provide constructor for eic::VectorXYZT from dd4pod::VectorXYZ and double
Creating an eic::VectorXYZT fourvector from a dd4pod mcparticles entry requires individual x,y,z setters. Ideally, we'd have
```code
for (const auto& p : mcparts) {
if (p.genStatus() == 4 && p.pdgID() == 11) {
// Incoming electron
eic::VectorXYZT ei(p.ps(), p.E());
break;
}
}
```
issue