Fix for HTTP_X_FORWARDED_FOR header
Fix for HTTP_X_FORWARDED_FOR header

The code was looking for X-Forwarded-For in the request headers, but
this is converted to HTTP_X_FORWARDED_FOR by Django, so we were in
fact logging a load balancer's IP and not the client.

sigshen/django-request-profiler,sigshen/django-request-profiler,yunojuno/django-request-profiler,yunojuno/django-request-profiler