add staticfield setter

WiFiManager.cpp

@@ -1012,6 +1012,11 @@ void WiFiManager::setRestorePersistent(boolean persistent) {
   if(!persistent) DEBUG_WM(F("persistent is off"));
 }
 
+void WiFiManager::setShowStaticFields(boolean alwaysShow){
+  _sta_show_static_fields = alwaysShow;
+}
+
+
 // HELPERS
 
 template <typename Generic>

WiFiManager.h

@@ -145,6 +145,8 @@ class WiFiManager
     void          setRemoveDuplicateAPs(boolean removeDuplicates);
     //setter for ESP wifi.persistent so we can remember it and restore user preference, as WIFi._persistent is protected
     void          setRestorePersistent(boolean persistent);
+    //if true, always show static net inputs, IP, subnet, gateway, if false, only show when already set.
+    void          setShowStaticFields(boolean alwaysShow);
 
   private:
     std::unique_ptr<DNSServer>        dnsServer;