+ gnuplot output file can be triggered with WITH_GNUPLOT_OUT macro
+ added Roter Pfeil functionality
* made output more readable
* fixed bug with sc_time_stamp() in Tramsignal.h
* train arrival can be triggered with TRAIN_ARRIVAL macro
+ gnuplot output can be created by calling 'make plot' (if WITH_GNUPLOT_OUT is enabled in defines.h)
* added all necessary graphs to plotfile.p