Auto set number of consignment boxes for courier integration/labels

This fantastic feature request was from @adam-henderson. I have split this from another thread with multiple suggestions into a single thread to ensure it can be tracked through to implementation properly and others voting know what they are voting for.

If you would find this useful, please give this thread a vote :+1:

Adding the idea here that when specifying your boxes, you could enter the dimensions of the box to ensure that Breww can pass over more specific dimensions to the courier when generating labels.