add button Description

Author: lewisxhe

README.MD

@@ -43,8 +43,12 @@ TTGO-Camera
 | Button | 34  |
 | PIR    | 33  |
 
-* ~~BUTTON : Reverse camera ,Currently the camera reverse color will not be normal, see [issues#9](https://github.com/espressif/esp32-camera/issues/9)~~
+* BUTTON Click: Reverse camera ~~Currently the camera reverse color will not be normal, see [issues#9](https://github.com/espressif/esp32-camera/issues/9)~~
+
+* BUTTON LongPress : Enter sleep Mode , Sleep current ~6.9mA
 
+* RESET BUTTON: When the battery is powered, click to turn on the power
+
 * PIR: Detecting human motion and will display the first screen