Clean up version of long track reconstruction based on SciFi seeding and Velo-SciFi matching (!742 (merged)).
The hlt1 reconstruction with seeding+track-matching can be enabled by using the hlt1_pp_matching or hlt1_pp_matching_validation sequences.
Information about the new tracking algorithms and the existing discussion can be found in !742 (merged) (which will be kept as a development branch).
@lohenry @lcalefic @ahennequ @bjashal @lpica @gligorov @dcampora @dovombru