[FIX] web_calendar: search date range when no date_stop field
[FIX] web_calendar: search date range when no date_stop field

microcom/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,laslabs/odoo,dfang/odoo,bplancher/odoo,ygol/odoo,Elico-Corp/odoo_OCB,microcom/odoo,dfang/odoo,storm-computers/odoo,ygol/odoo,laslabs/odoo,hip-odoo/odoo,storm-computers/odoo,storm-computers/odoo,dfang/odoo,laslabs/odoo,bplancher/odoo,storm-computers/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,ygol/odoo,hip-odoo/odoo,ygol/odoo,hip-odoo/odoo,microcom/odoo,Elico-Corp/odoo_OCB,bplancher/odoo,ygol/odoo,microcom/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,dfang/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo,Elico-Corp/odoo_OCB,laslabs/odoo,laslabs/odoo,microcom/odoo,laslabs/odoo,dfang/odoo,microcom/odoo,storm-computers/odoo