trytond: Use one getter for all amounts in Sale, Purchase and Invoice (issue 897002)

[cedric...@b2ck.com]

Reviewers: ,



Please review this at http://codereview.tryton.org/897002/

Affected files:
M trytond/modules/account_invoice/invoice.py
M trytond/modules/purchase/purchase.py
M trytond/modules/sale/sale.py

[Cédric Krier]

I would like to bring your attention on the removal of the final
rounding. For me, it was not needed because it is just the sum rounded
Decimal which should still be rounded.

--
Cédric Krier

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