[FIX] compatibility with pos_restaurant https://github.com/OCA/pos/pull/339 cortesy @carlosDomatix
[FIX] add _compute_refund_order_qty
[ADD] pos order view form. Add links to original returned order and refund orders.
[IMP] when refunding an order via the 'Refund' button in back office, set the correct returned_order_id.
[IMP] Add helper on each button
[ADD] python test
[REF] JS remove useless code
[REF] Python remove useless code
[FIX] remove bad oldname
[FIX] remove gap in bill display, when it is a refund
[FIX] when reprinting a bill, the returned order name is displayed, if any
[FIX] JS lint, with OCA eslint file
[ADD] french translation
When the PoS is using fiscal positions it can lead to errors when
computing the reprinted ticket value because the tax mapping function
computes them from the current order instead of from the one belonging
to the line. So we set our loaded order temporarily as the selected one
just to bring it back to the current one after it's printed.