update mixpanel indetify code. See https://mixpanel.com/help/reference/javascript-full-api-reference#mixpanel.identify for reference
update mixpanel indetify code. See https://mixpanel.com/help/reference/javascript-full-api-reference#mixpanel.identify for reference

bittner/django-analytical,jcassee/django-analytical,ericdwang/django-analytical,machtfit/django-analytical,apocquet/django-analytical,ChristosChristofidis/django-analytical,pjdelport/django-analytical