[FIX] web_calendar: Do not display empty values in displayed text in calendar view cells
[FIX] web_calendar: Do not display empty values in displayed text in calendar view cells

akretion/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web