properly close transaction overlay after adding an transaction
properly close transaction overlay after adding an transaction

Close #584

aumayr/beancount-web,aumayr/beancount-web,yagebu/fava,beancount/fava,yagebu/fava,yagebu/fava,yagebu/fava,beancount/fava,aumayr/beancount-web,beancount/fava,yagebu/fava,aumayr/beancount-web,beancount/fava,beancount/fava