add a health check endpoint to nginx.

NginxDefault

@@ -22,8 +22,14 @@ server {
 
         # deny access to .htaccess files, if Apache's document root
         # concurs with nginx's one
-        #
         location ~ /\.ht {
                deny all;
         }
+
+        # Health check endpoint
+        location /health {
+            access_log off;
+            add_header 'Content-Type' 'application/json';
+            return 200 '{"status":"Healthy"}';
+        }
 }