Liquids and gases disappear from trucks

Issue description

All liquids and gases except chlorine, crude oil, diesel and fuel gas disappear from trucks when there is no available storage.

Reproduction steps

1. Build a storage and fill it with liquid or gas, except those mentioned.
2. Build an empty storage and assign the same product.
3. In a filled storage click to remove currently assigned product or move slider for empty by trucks.
4. After loading the trucks, pause the empty storage. Trucks are emptied instantly and the empty storage will fill up.
5. If you don't pause but delete the assigned product in an empty storage, the product will simply disappear.

Game version and build number

v0.6.4 (b337)

Operating system

Windows

There's a difference between the fluids. Diesel, chlorine, oil, etc. are harmfull for the enviroment. Thats why u have to take care of them. Thats why they don't just disappear.
Water, hydrogen, brian, O2, etc. are harmless and will be just "dumped".

This is a bug, they should not just disappear, they should be moved to the shipyard.