Fixed buy menu groups, lights and the fan animation (finally for real this time, I promise!)

fixed buy meny groups courtesy of user Jeroezie

Small texture bugfix

Added; lights fixed; distance between units, overhang of the railing, buffer shape

new workshop and in-game thumbnails

fixed some issues with definitions of materials

added a buy menu group, driver if the train is reversed, and some other minor adjustments

Added exhaust particles, fixed thumbnails, other minor corrections

First test version