Added number of subtrips per person and total length of subtrips per person. Added more structured section headlines.
Added total length of subtrips per grouped transportation mode and total length of subtrips per transportation mode. Cleaned up code.
Cleaned up code.
Fixed small bugs. Cleaned up code.
Added mean to plot #05.
Added "started subtrips per hour" and "started subtrips per hour and transportation mode".
Added "started subtrips per hour and transportation mode".