Gets the birth/death events instead of sampling the database. The "NOTHING" curve is not needed any more

Only gnuplot has to know about the filtered analysis, the CSV file should still contain all the data

schema_change: detect and register RELOCATED events that used to mess up things on LSF 9.0 ("job rescheduled" in LSF parlance)

be more careful with fetch_overdue_workers (Use 5sec threshold to avoid checking recently active Workers. Do not use it at all when performing -all_dead.)

bugfix:  last_check_in should only be updated by register_worker_death if the Worker is burying itself

cosmetic: added (commented out) warning messages for every external system() call that LSF module runs - simplifies debugging a lot