Not possible to create standalone invoice lines

Creating a new invoice_line is not possible, every field is read-only.

(further readings: http://www.tryton.org/~irclog/2017-01-31.log.html#t2017-01-31%2009:52)

Expected behaviour: fields are not read-only but allow selecting a party, product, etc.

added 1 deleted label

Since changeset4058a9914245

Here is review27071002 which fixes it.

assigned to @pokoli

added 1 deleted label and removed 1 deleted label

review27071002 updated at https://codereview.tryton.org/27071002/#ps1

patching /trytond/modules/account_invoice/invoice.py did it.
works now.

review27071002 updated at https://codereview.tryton.org/27071002/#ps20001

review27071002 updated at https://codereview.tryton.org/27071002/#ps30001

review27071002 updated at https://codereview.tryton.org/27071002/#ps50001

New changeset 806f27bafbda by Sergi Almacellas Abellana in branch 'default':
Add default invoice state on Invoice Lines
http://hg.tryton.org/modules/account_invoice/rev/806f27bafbda

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closed

New changeset d0e87dacffa1 by Sergi Almacellas Abellana in branch '4.2':
Add default invoice state on Invoice Lines
http://hg.tryton.org/modules/account_invoice/rev/d0e87dacffa1