RichDetailedTrSegMakerFromTracks : Minor overhaul to improve CPU performance

• Switch by default to STEP track extrapolator, to move states. Previously was Runge Kutta.
• Rework the algorithm to remove a number of redundant calls to extrapolator and volume intersection tools.
• Compute the primary mirror exit state correction before the beam pipe intersection check (RICH1). Helps with code optimisation (lets me remove one state move) but also I think makes more sense physically.

All in, algorithm should be significantly faster (perhaps as much as twice as fast).

@cattanem Diffs expected here, due to real changes in what the algorithm does. Should be more than just machine precision but not 'huge'. Test at your convenience and I will check any diffs as required.