Synchronise the “Laycan From” and “Laycan To” columns between the Itinerary and the Cargo header.

When CFGEnableItinLaycanFields is enabled it adds laycan fields to Cargo/Itinerary tab, however these fields have to be manually updated as well as the laycan fields on the cargo header. This is unnecessary double entry and seeing different values at cargo header and load port itinerary line is misleading (at best). Suggest that the cargo header laycan dates should be sync'd with the itinerary dates on (first) loading port call line.