FRANKFURT (Reuters) - German restaurant chain Vapiano SE on Friday said it was insolvent and would apply for government assistance to avoid formally filing for insolvency, blaming the coronavirus crisis for a drop in sales. "Due to the drastic decline in net sales and revenues, an insolvency reason in the form of cash flow insolvency for Vapiano SE has occurred as of today," the company said.Vapiano's 55 German restaurants were closed yesterday evening, and almost all of the chain's more than..