improve documentation(#524)

add wifi manager portal screenshots
add M5stick
correct bad link
improve lora doc

docs/.vuepress/config.js

@@ -62,7 +62,8 @@ module.exports = {
             'upload/binaries',
             'upload/pio',
             'upload/arduino-ide',
-            'upload/portal'
+            'upload/portal',
+            'upload/troubleshoot'
           ]
         },
         {