Update v180306 Changelog:
_________________________________________

• Multiple bug fixes and improvements to level editing mode.
• Undo/redo history now works for changing object position and orientation.
• Trucks are now better visualised on the map. Truck/trailer/addon picker dialog added.
• Truck orientation can now be arbitrary. (Trucks are no longer required to be landed.)
• Mods can now contain levels that are properly exported to the workshop.
• Improvements were made to the "import spintires-2016 level" function.
• Truck textures are now better optimised when exporting to the workshop.
• Added "default screenshot for the item" function added for mods.