BULK TRADER - Updates

Loads of updates from tuning the returns on cargoes, changing the financing system, and added some more destinations and vessel sizes, as well as soybean meal !

Crucially added harvest seasonality - so in the harvest months... prices will be lower, and right before harvests prices will be at their highest - mostly.

Some minor updates to fuel mechanics will come next, before some larger expansion to add CPT markets and Grain Silos. 

Shipowning and time-charter re-lets will come next after that !