Changes made:
- Both subclasses now have the same sounds
- Both subclasses now have the same top-speed of 75mph
- A different 313 is now required for the 455/7 subclass to work, please check description for more information
- Fixed a bug regarding the 455 not appearing in the trains menu
- Fixed a bug regarding the 455 not having a "powered locomotive"
- The 455 now has its own menu separated from the 317