Fix 2019 MC Recon steering file to use the useTimestamps instead of subtractTriggerTime

[bloodyyugo]

The current 2019/2021 MC recon steering file has useTimestamps turned off and subtrackTriggerTime turned on in the RawTrackerHitFitterDriver part...it should be the opposite (and even says so in the comments).

I'm not sure why it's got set this way, probably copied from a recon steering file.

This issue is to fix that and make it like the other MC steering files (e.g. 2016)

[bloodyyugo]

Actually, that's not the best one to use since it has a bunch of seed tracker stuff. I copied over the one I was using for the unspaced MC development and added in Rory's changes to the hit fitting, clustering.