[FIX] point of sale: sign of amount tax
[FIX] point of sale: sign of amount tax

When creating a tax movement, the sign of the amount tax must be
the tax_sign in the normal case or ref_tax_sign in the refund case.
Inspired from the function create defined in model "account.move.line"

opw:658378

BT-rmartin/odoo,Elico-Corp/odoo_OCB,laslabs/odoo,CatsAndDogsbvba/odoo,Endika/odoo,glovebx/odoo,odootr/odoo,jfpla/odoo,factorlibre/OCB,mustafat/odoo-1,MarcosCommunity/odoo,synconics/odoo,grap/OpenUpgrade,rubencabrera/odoo,synconics/odoo,ygol/odoo,Endika/OpenUpgrade,hip-odoo/odoo,hassoon3/odoo,jfpla/odoo,hassoon3/odoo,CatsAndDogsbvba/odoo,factorlibre/OCB,provaleks/o8,leorochael/odoo,NeovaHealth/odoo,spadae22/odoo,grap/OpenUpgrade,eino-makitalo/odoo,MarcosCommunity/odoo,BT-rmartin/odoo,funkring/fdoo,glovebx/odoo,shingonoide/odoo,Adel-Magebinary/odoo,hip-odoo/odoo,NeovaHealth/odoo,laslabs/odoo,bplancher/odoo,eino-makitalo/odoo,makinacorpus/odoo,NeovaHealth/odoo,datenbetrieb/odoo,hassoon3/odoo,factorlibre/OCB,Daniel-CA/odoo,shingonoide/odoo,funkring/fdoo,synconics/odoo,vnsofthe/odoo,Daniel-CA/odoo,markeTIC/OCB,sysadminmatmoz/OCB,grap/OpenUpgrade,markeTIC/OCB,storm-computers/odoo,BT-ojossen/odoo,MarcosCommunity/odoo,odootr/odoo,diagramsoftware/odoo,funkring/fdoo,sergio-incaser/odoo,BT-ojossen/odoo,alexcuellar/odoo,CatsAndDogsbvba/odoo,jiangzhixiao/odoo,Endika/OpenUpgrade,MarcosCommunity/odoo,makinacorpus/odoo,jfpla/odoo,NeovaHealth/odoo,Endika/odoo,glovebx/odoo,BT-rmartin/odoo,ehirt/odoo,alexcuellar/odoo,hassoon3/odoo,markeTIC/OCB,leorochael/odoo,mustafat/odoo-1,Noviat/odoo,funkring/fdoo,hip-odoo/odoo,jfpla/odoo,datenbetrieb/odoo,alexcuellar/odoo,Adel-Magebinary/odoo,Noviat/odoo,hip-odoo/odoo,shingonoide/odoo,stephen144/odoo,jfpla/odoo,ehirt/odoo,synconics/odoo,Adel-Magebinary/odoo,provaleks/o8,diagramsoftware/odoo,Endika/OpenUpgrade,CatsAndDogsbvba/odoo,rubencabrera/odoo,jiangzhixiao/odoo,sergio-incaser/odoo,Endika/odoo,vnsofthe/odoo,rubencabrera/odoo,Nowheresly/odoo,factorlibre/OCB,Daniel-CA/odoo,ygol/odoo,diagramsoftware/odoo,Adel-Magebinary/odoo,grap/OpenUpgrade,synconics/odoo,datenbetrieb/odoo,OpenUpgrade/OpenUpgrade,Noviat/odoo,makinacorpus/odoo,grap/OpenUpgrade,eino-makitalo/odoo,microcom/odoo,tvibliani/odoo,glovebx/odoo,CatsAndDogsbvba/odoo,eino-makitalo/odoo,ehirt/odoo,BT-rmartin/odoo,diagramsoftware/odoo,mustafat/odoo-1,Nowheresly/odoo,diagramsoftware/odoo,sysadminmatmoz/OCB,ygol/odoo,Endika/OpenUpgrade,leorochael/odoo,stephen144/odoo,bplancher/odoo,Endika/odoo,NeovaHealth/odoo,markeTIC/OCB,rubencabrera/odoo,microcom/odoo,storm-computers/odoo,Nowheresly/odoo,jiangzhixiao/odoo,glovebx/odoo,OpenUpgrade/OpenUpgrade,storm-computers/odoo,OpenUpgrade/OpenUpgrade,ehirt/odoo,diagramsoftware/odoo,jiangzhixiao/odoo,makinacorpus/odoo,Daniel-CA/odoo,spadae22/odoo,factorlibre/OCB,Elico-Corp/odoo_OCB,BT-ojossen/odoo,shingonoide/odoo,provaleks/o8,CatsAndDogsbvba/odoo,markeTIC/OCB,BT-ojossen/odoo,mustafat/odoo-1,Noviat/odoo,Elico-Corp/odoo_OCB,grap/OpenUpgrade,tvibliani/odoo,bplancher/odoo,ygol/odoo,alexcuellar/odoo,Elico-Corp/odoo_OCB,leorochael/odoo,BT-rmartin/odoo,OpenUpgrade/OpenUpgrade,microcom/odoo,tvibliani/odoo,sysadminmatmoz/OCB,dfang/odoo,storm-computers/odoo,sergio-incaser/odoo,synconics/odoo,sergio-incaser/odoo,ehirt/odoo,Daniel-CA/odoo,draugiskisprendimai/odoo,rubencabrera/odoo,sysadminmatmoz/OCB,leorochael/odoo,funkring/fdoo,Daniel-CA/odoo,sergio-incaser/odoo,sergio-incaser/odoo,draugiskisprendimai/odoo,spadae22/odoo,factorlibre/OCB,funkring/fdoo,laslabs/odoo,jfpla/odoo,eino-makitalo/odoo,OpenUpgrade/OpenUpgrade,provaleks/o8,MarcosCommunity/odoo,dfang/odoo,bplancher/odoo,Endika/odoo,odootr/odoo,odootr/odoo,vnsofthe/odoo,vnsofthe/odoo,stephen144/odoo,MarcosCommunity/odoo,jiangzhixiao/odoo,microcom/odoo,spadae22/odoo,microcom/odoo,ygol/odoo,hassoon3/odoo,draugiskisprendimai/odoo,hassoon3/odoo,odootr/odoo,spadae22/odoo,jiangzhixiao/odoo,tvibliani/odoo,eino-makitalo/odoo,dfang/odoo,glovebx/odoo,draugiskisprendimai/odoo,jiangzhixiao/odoo,dfang/odoo,CatsAndDogsbvba/odoo,stephen144/odoo,sysadminmatmoz/OCB,mustafat/odoo-1,OpenUpgrade/OpenUpgrade,dfang/odoo,ygol/odoo,bplancher/odoo,makinacorpus/odoo,odootr/odoo,Adel-Magebinary/odoo,Nowheresly/odoo,stephen144/odoo,BT-ojossen/odoo,diagramsoftware/odoo,storm-computers/odoo,BT-ojossen/odoo,alexcuellar/odoo,BT-rmartin/odoo,NeovaHealth/odoo,Endika/odoo,Daniel-CA/odoo,tvibliani/odoo,markeTIC/OCB,shingonoide/odoo,draugiskisprendimai/odoo,datenbetrieb/odoo,bplancher/odoo,grap/OpenUpgrade,laslabs/odoo,odootr/odoo,BT-rmartin/odoo,Elico-Corp/odoo_OCB,Noviat/odoo,OpenUpgrade/OpenUpgrade,Noviat/odoo,Nowheresly/odoo,ehirt/odoo,draugiskisprendimai/odoo,storm-computers/odoo,markeTIC/OCB,leorochael/odoo,provaleks/o8,vnsofthe/odoo,Endika/OpenUpgrade,ygol/odoo,datenbetrieb/odoo,alexcuellar/odoo,Adel-Magebinary/odoo,NeovaHealth/odoo,laslabs/odoo,spadae22/odoo,eino-makitalo/odoo,datenbetrieb/odoo,vnsofthe/odoo,hip-odoo/odoo,rubencabrera/odoo,sysadminmatmoz/OCB,provaleks/o8,glovebx/odoo,makinacorpus/odoo,dfang/odoo,jfpla/odoo,factorlibre/OCB,shingonoide/odoo,provaleks/o8,alexcuellar/odoo,Nowheresly/odoo,sysadminmatmoz/OCB,datenbetrieb/odoo,hip-odoo/odoo,Elico-Corp/odoo_OCB,draugiskisprendimai/odoo,mustafat/odoo-1,Noviat/odoo,vnsofthe/odoo,makinacorpus/odoo,shingonoide/odoo,mustafat/odoo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