[IMP] api: compute methods cannot depend on field 'id'

This feature hasn't been implemented because of complexity problems.
Therefore, we should not allow the developer to use it.
[FIX] web: do not check if db in session match filter if no db
[MERGE] forward port of branch saas-3 up to 685fa26
[MERGE] forward port of branch saas-5 up to 9699f62
[FIX] website_hr_recruitment: add param to force all countries else it use GeoIP, check that country returned by GeoIP have jobs availables else fallback on all countries
Merge branch '8.0' of https://github.com/odoo/odoo into 8.0-linux64