update Xcode project, fix some warnings, update android icons, ignore unrecognized files in the doc browser

src/node_combobox.cpp

@@ -88,5 +88,7 @@ void NodeComboBox::parse_attributes(kAttribute ka, const tinyxml2::XMLAttribute*
     case kAttribute::Default:
         m_current_index = attr->IntValue();
         break;
+    default:
+        break;
     }
 }