Mark's Flatbed Cargo Variety for ATS 1.43

This mod aims to add the so-much-needed variety to the flatbed cargo, providing a bit better experience when hauling flatbed cargo. The mod adds new variants to the original cargo, as well as brand new cargo (some of them are also ported from ETS2).

14 March 2022:

- Added 2 new cargoes for lowboy trailers

- Some other adjustments and improvements