[FIX] calendar/crm: Add active_id (if in model partner_id) in defaults values from partner_ids when we creates a new meeting.

Bug was that when you click on meeting button from a res_partner form (Customers in menu), the button overwrites the context to use the active partner as a default in the calendar meeting. By consequence, the context overwritte the default partner who are the creator. Now the context could be removed from action and that is in get_default for partner_ids (from model calendar_event) that we add the creator AND the active_id if from a model res_partner.