Review members and their precision in new Track class

The following discussion from !1533 (merged) should be addressed:

@sstahl started a discussion: (+1 comment)

Remove Likelihood and ghostprobability as they are only set after the track fit.
Remove TrackFitResult
Remove extra info

I think these can be trivially removed as they are not used anywhere or only in or two places and then the use is questionable, e.g. using extra info in PrForward.

Review the other members.

Edited Nov 26, 2018 by Sascha Stahl

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information