OpenBVE v1.7.1.0

This is another relatively major release, primarily implementing the first version of a new openGL 3.1 renderer.

Changes:

• New (optional) openGL 3.1 renderer.
• New: Improve the distance to next station display when the next station is not a stop.
• Fix: A train.dat file edited with Excel would not be recognised.
• Fix: Visibility broken for objects spanning more than one block in the reverse direction.

Update:

Mac download temporarily rolled back to 1.7.0.3 due to issues with the openGL context. Will push a fixed version as soon possible.