[FIX] im_livechat: fixed missing access rules for portal users.
[FIX] project_issue_sheet: timesheet_ids visible only for employees, because currently portal members have no access rights on hr.analytic.timesheet.
[FIX] portal: allow reading any partner belonging to the same entity
[FIX] project_issue: improved form view for portal users; now have basic info in addition to ID.