- Added the ball signal.
- Ball and disc signals available 1850 - 1890.
- Price adjustment to disc signal.

The Ball signal was one of the earliest railroad signals used as early as in the mid 1930. It was a bit odd because "Green" wa the upper position and "red" the lower position. The color of the ball could be different; Red, Black or White. It was the ball's position, not color, that indicated the state.

The disc signal's price has been changed from 1500 to 1350 and is available to 1890.

Fixed a texture issue causing crash on some systems