Add sale_bom_split_dropshipping: compatibility module

[guewen]

Between sale_bom_split and sale_dropshipping.

• _sale_bomsplit splits the bill of materials in the delivery orders when a sales order is confirmed
• _saledropshipping allows to use dropshipping on sales order lines (no picking, creates "on order" procurements)

When both modules are installed, the components of the BoM are added in the normal picking even if the line is set to "dropshipping". With this compatibility module, the components are well considered as dropshipped and are not added in the picking, but have "on order" procurements.

[mdietrichc2c]

There was an issue in the refactoring: the picking_id was not assigned after _create_components_moves_and_procurements, which meant that 2 pickings were created, and the first one was never confirmed.

[guewen]

I used git rebase -i to clean the history

[pedrobaeza]

As Travis is red and no fix, I close. Feel free to reopen in case there's interest.