charts: draw to svg not div; cleanup
charts: draw to svg not div; cleanup

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