added parameter with HTTP headers used to determine the protocol scheme behind nginx proxy

Change-Id: I4d781928ad22781f357feaae6de044c9a70b14dd
diff --git a/cinder/files/mitaka/cinder.conf.controller.Debian b/cinder/files/mitaka/cinder.conf.controller.Debian
index 24aed63..344ec83 100644
--- a/cinder/files/mitaka/cinder.conf.controller.Debian
+++ b/cinder/files/mitaka/cinder.conf.controller.Debian
@@ -204,3 +204,6 @@
 {%- if controller.cors.allow_headers is defined %}
 allow_headers = {{ controller.cors.allow_headers }}
 {%- endif %}
+
+[oslo_middleware]
+secure_proxy_ssl_header = X-Forwarded-Proto
\ No newline at end of file