Event catalogue changed + minor changes of shell output.

The event catalogue, which is derived for non continuous requests, is now available for interactive deletion of events if the executing persons wants it. Specifically, the program flow changed to:

     if len(events) <= 10: 
          print all events, ask if deletion is wanted, proceed
     elif len(events) > 10: print first and last 2 events, ask if all events want to be seen 
         (if so: ask if deletion wanted, if not: assume no deletion is wanted), proceed