Produce proper associations from Particles to MCParticles in TracksToParticles

[veprbl]

Is your feature request related to a problem? Please describe.
The current TracksToParticles algorithm uses geometric matching and is not very suitable for tracking studies.

Describe the solution you'd like
TracksToParticles uses information about hit origin to infer which MCParticle was the leading cause for its existence.

Describe alternatives you've considered
None

Additional context
This was discussed in Reco WG meeting
Some groundwork is laid in #1392 by @bschmookler