[REM] most uses of `self.pool`

addons/mail/models/mail_message.py

addons/mail/models/mail_template.py

addons/mail/models/mail_thread.py

addons/mail/models/res_partner.py

addons/mail/models/res_users.py

addons/mail/wizard/invite.py

addons/mail/wizard/mail_compose_message.py

addons/stock_account/models/stock.py

addons/stock_calendar/models/resource.py

addons/website/models/ir_http.py

openerp/addons/base/ir/ir_actions.xml

openerp/addons/base/ir/ir_values.py

openerp/models.py