update nginx, set wan interface for wo dashboard

wo/core/variables.py

@@ -22,6 +22,13 @@ class WOVariables():
     if wo_wpcli_path == '':
         wo_wpcli_path = '/usr/local/bin/wp '
 
+    # get wan network interface name
+    wo_wan_interface = os.popen("ip -4 route get 8.8.8.8 | "
+                                "grep -oP \"dev [^[:space:]]+ \" "
+                                "| cut -d ' ' -f 2").read()
+    if wo_wan_interface == '':
+        wo_wan_interface = 'eth0'
+
     # Current date and time of System
     wo_date = datetime.datetime.now().strftime('%d%b%Y%H%M%S')