[FIX] web: stages positioned properly when there is no sheet

Fixes #271
Closes #2004
[FIX] ir_attachment: attachements removed on record unlink
[FIX] point_of_sale: fix some image chaching issues with the receipt logo. Using a random url at each fetch ensures that we don't get cached results
[FIX] point_of_sale: chrome was dropping the cookie when loading the company logo, resulting in an incorrect logo in multi-db setups.
[FIX] mail: alias domain should be fetch as superuser

as ir.config.parameter has limited access
[FIX] mail: encoding of sender name with unicode

When sending an email, both formats 'Name <email>' or '"Name" <email>' can be used for fields 'From', 'To' and others. If the name contains unicode characters, a regex only matching '"Name" <email>' was used to encode the name with RFC2047. That meant that the name was not encoded and eventually dropped, using only the email part.
Instead of using a limited regex, use the parseaddr method from email library.
Fixes lp:1272610, opw 607683
[FIX] web: *.openerp.com to *.odoo.com
[FIX] hr_expense: tax amount computation

The tax_amount field should contain the basic amount (without tax) for base tax code. (opw 613470)
[FIX] web_graph: pivot_table, use _.isEmpty to check if value_lookup is False
[FIX] survey: access rights error when editing

The wizard 'Edit Survey' > 'Add Question' was trowing an access rights error as the id was passed as a string instead of a real id. opw 607854
[FIX] stock: return picking, pass serial number value when returning
[FIX] web: sort with undefined value

In this awesome programming language called javascript, undefined is neither bigger nor smaller than a string. Previous code was then considering undefined values equal to any string.
This fix allows to sort in a column of a o2m field and group the undefined values together. opw 607704
[FIX] product: can be sold as default filter for templates
[FIX] l10n_ro: backport of fix done in res_partner.py from aa76885

PR #720
[FIX] mrp_repair: invoice the actual invoice partner id
[MERGE] forward port of branch 7.0 up to 9b1cdea
[IMP] ir.model:.fields allow setting ondelete=restrict foncustom fields
[FIX] tools: restrict available attributes
[MERGE] forward port of branch 7.0 up to b601015
[FIX] web: backport of ebb826a and 2372d30

Fixing breadcrumb not being displayed after some action button (e.g. validate invoice, opw 612763)