[FIX] models, fields: add model dependencies for models backed up by sql views
[IMP] models: add an extension mechanism for attribute _depends on models
[IMP] addons: add _depends on models backed up by an sql view and used by other models
[IMP] fields: add missing case for invalidating fields, when path is None
[IMP] fields: improve code in former commit
[FIX] account_analytic_analysis: fix _depends
Merge pull request #989 from odoo-dev/8.0-sql-models-rco

[FIX] models, fields: add model dependencies for models backed up by sql views
[IMP] Crm: Add tracking mixin to manage utm campaign and add this mixin to mass_mailing, crm_lead and sale_order