use session storage for django messages
use session storage for django messages

fixes india server cookie error that prevents people from using the site
indefinitely (until cookies are cleared) after a django message is set
that has html content

dimagi/commcare-hq,dimagi/commcare-hq,qedsoftware/commcare-hq,qedsoftware/commcare-hq,puttarajubr/commcare-hq,SEL-Columbia/commcare-hq,dimagi/commcare-hq,qedsoftware/commcare-hq,dimagi/commcare-hq,puttarajubr/commcare-hq,dimagi/commcare-hq,puttarajubr/commcare-hq,qedsoftware/commcare-hq,qedsoftware/commcare-hq,SEL-Columbia/commcare-hq,SEL-Columbia/commcare-hq,puttarajubr/commcare-hq