Add minimum momentum cut in hybrid seeding

See !3409 (comment 6731059)

@jonrob

Without cut:

SeedTrackChecker_6f38a9cb              INFO Results
SeedTrackChecker_6f38a9cb              INFO **** Seed                             9558 tracks including            479 ghosts [ 5.01 %], Event average  4.82 % ****
SeedTrackChecker_6f38a9cb              INFO   01_hasT                        :    6497 from     7781 [ 83.50 %]      0 clones [ 0.00 %], purity: 99.56 %, hitEff: 98.00 %
SeedTrackChecker_6f38a9cb              INFO   02_long                        :    4642 from     4960 [ 93.59 %]      0 clones [ 0.00 %], purity: 99.70 %, hitEff: 98.60 %
SeedTrackChecker_6f38a9cb              INFO   03_long_P>5GeV                 :    3291 from     3420 [ 96.23 %]      0 clones [ 0.00 %], purity: 99.67 %, hitEff: 99.09 %

With cut at 4500:

SeedTrackChecker_6f38a9cb              INFO Results
SeedTrackChecker_6f38a9cb              INFO **** Seed                             6894 tracks including            284 ghosts [ 4.12 %], Event average  3.88 % ****
SeedTrackChecker_6f38a9cb              INFO   01_hasT                        :    4998 from     7781 [ 64.23 %]      0 clones [ 0.00 %], purity: 99.55 %, hitEff: 98.67 %
SeedTrackChecker_6f38a9cb              INFO   02_long                        :    3816 from     4960 [ 76.94 %]      0 clones [ 0.00 %], purity: 99.69 %, hitEff: 99.04 %
SeedTrackChecker_6f38a9cb              INFO   03_long_P>5GeV                 :    3292 from     3420 [ 96.26 %]      0 clones [ 0.00 %], purity: 99.67 %, hitEff: 99.09 %

I will be very curious to see the speedup. The cut is done at the earliest possible level and so the speedup is probably much, much better than nTracks(cut)/nTracks(without cut). I am more expecting a factor 4 or so, and if needed I can provide an even faster version (factor 2 or more), but this will start actually cutting slightly on performance.