[FIX] stock: groups mixup in views

Use group_production_lot for serial options, group_stock_packaging for packaging, use group_tracking_lot for pallet/parcel
Groups are removed completly from the view for stock.tracking as they render the view useless.

Always display weights on the product form
They really have nothing to do with the logistic units and we don't have another group to restrict them to.

Fixes #1443
[ADD] l10n_lu: abbreviated financial reports

Abbreviated version of the p&l and balance sheet reports
[FIX] account: self typo
[FIX] gamification: on delete badge user, cascade

Otherwise, this is no more possible to delete users having badges
[FIX] ir.ui.view: creating custom views in backend did not compute view type

When creating new records in backend all field values are
sent to the server, including empty fields.
[FIX] account: precision_get returns a number of digits

In other words, it returnes a precision digits, not a precision rounding
[MERGE] forward port of branch 7.0 up to 03df412f
[IMP] mail: parsing emails with several html parts

If an email contains several text/html parts inside a multipart email, the previous code was only keeping the last content part.
The Content-Type: multipart/mixed allows several independent part (RFC1341 7.2.2), so two html is technically valid.
With this patch, the two parts are concatenated. (opw 614755)

Modify append_content_to_html regex to make sure the regex keeps the content of the html instead of removing it.
e.g.: "123 <html> 456 </html> 789" used to be stripped to "123  789" while we expect "123 456 789"
[FIX] point_of_sale: printing of tax name on hardware was missing data 'name', also made the regular print use the same value for consistency.
[FIX] res.users: exactly match login when operator in ilike, equal
[FIX] account_invoice: using has_group to determine if user has group group_supplier_inv_check_total

has_group do not care about the fact res.groups is access restricted
[FIX] ir.mail.server: restore parsing of multiple RFC2822 addresses including non-ASCII chars

Rev f2cf6ced1 modified RFC2822 parsing in order to better support
unicode characters inside the Name part of an address header.
However the patch broke handling of multiple addresses (comma
separated) - silently discarding all recipients except the
first one, as soon as any non-ASCII character was present.

This patch restores the functionality while preserving the
fix from f2cf6ced1, and simplifies the code using email.utils
utility functions.

Fixes (again) lp:1272610, OPW 607683
[MERGE] Forward-port 7.0 up to 1b49a87
[FIX] website_membership: crash when member has no country

in memberships countries list
[FIX] web: wait for deferreds when actualizing mode

In edit mode, in a *2many with many2many_tags, when adding a new tag when none was set, discarding the form let the new tags displayed while it shouldn't (only a display issue, the tag wasn't added in database)

Fixes #2926
[FIX] email_template: do not try to add user signature if none set

append_content_to_html expects two strings. If the user has no signature, it returns user.signature returns False
[FIX] point_of_sale: fixed display of untaxed amount in sales lines report
[MERGE] forward port of branch 7.0 up to 75d3ea6
[MERGE] forward port of branch saas-3 up to db75994
Merge pull request #3001 from Bubbles-IT/8.0-fix-pos-tax-label

[FIX] point_of_sale: printing of tax name on hardware was missing name