[FIX] mrp: better selection of bom

When searching for a bom based on a product.product, the method used to return any bom linked to the template (so searching for bom for variant A could return bom for variant B if both share the same product.template).
This will allow to return bom not linked to a variant without returning the one of another variant (opw 609358)
[FIX] account: fix unexpected invalidation of field account_invoice.reconciled

Problem: the field account_invoice.reconciled was invalidated by a workflow
signal sent from the compute method of the field. The purpose of the signal was
to re-open the invoice when the account move lines were no longer reconciled,
for instance after cancelling a reconciliation.

Solution: modify the workflow such that it makes an automatic transition from
'paid' to 're-open' when the condition 'not reconciled' is met. This works
because the field 'reconciled' is stored, and each recomputation forces a
reevaluation the workflow. The signal to re-open the invoice is thus no longer
necessary.
[FIX] website_forum: when a user posting a new answer or question does not have a valid email address, redirect to the user's profile instead of crashing when trying to send notifications.
[FIX] mrp: Fix spelling error on 'manufacturing'

Changing .po files to avoid to retranslate existing terms.
Fixes #1328
Merge pull request #1581 from odoo-dev/8.0-fix-account-invoice-rco

[FIX] account: fix unexpected invalidation of field account_invoice.reconciled
[IMP] workflow: add sequence for ordering workflow transitions (split/join mode especially for XOR)

Makes ordering transitions easier and more deterministic.

(Rebase of #1564)
[FIX] web: tooltip container set to body in all case

Mandatory since we changed the structure of the dom since 8.0.
[IMP] point_of_sale: add an error sound to the error popups
[IMP] point_of_sale: a little explaination of how the barcode pattern system works
[IMP] point_of_sale: improved rendering speed of the partner list
[FIX] point_of_sale: order invoicing was broken
[FIX] point_of_sale: it was impossible to delete a pos session
[IMP] point_of_sale: show traceback popup when there is a server error when posting orders (which should NEVER happen !)
[IMP] point_of_sale: add debug popup that displays unsent order data, for when localStorage is hard to inspect

Conflicts:
	addons/point_of_sale/static/src/js/widgets.js
[IMP] point_of_sale: add a debug option to delete all unsent orders
[IMP] point_of_sale: add a basic UI unit test based on the new 'Tour' module
[IMP] point_of_sale: forgot changes in this file in the previous commit that introduced unit tests
[IMP] point_of_sale: tests work better when they are loaded and run by the unit test system!
[IMP] point_of_sale: made the server data loading more modular for easier development of point_of_sale extensions
[IMP] point_of_sale: report errors when loading the point of sale with a traceback and a nice popup