Updated TRD trigger code. Now the trigger code can run:

Updated TRD trigger code. Now the trigger code can run:

- in the simulation step, through the central trigger interface, to
produce and store "tracklets" and to produce and analyze tracks, with
inputs to the central trigger

- in the reconstruction step: if the tracklets have already been produced
in the simulation step (by the trigger option), then only the tracks are
produced and stored in the ESD event; if not, the trigger start by
producing the tracklets, etc.

Bogdan