Production release 4.8.1

Implemented enhancements:

• Support for non-ASCII onestop ids #579

Fixed bugs:

• RouteStopPattern creation error in f-dpmg-rta #573

Closed issues:

• Onestop Id exceptions #583
• Onestop Id Invalid Geometry Hash #575

Merged pull requests:

• Onestop ID exceptions, name fallbacks #582 (irees)
• Unicode onestop ids #580 (doublestranded)
• Handle trips one stop time #577 (doublestranded)
• Onestop id name truncation #576 (doublestranded)
• production release 4.8 #574 (drewda)