MAX7219 dot matrix, fix for (PR #1307)

docs/MAX7219.md

@@ -1,16 +1,17 @@
 # MAX7219 driver for multiple 8x8 dot matrix modules
+
+??? failure "This feature is not included in precompiled binaries"  
+
+    When [compiling your build](Compile-your-build) add the following to `user_config_override.h`:
+    ```arduino
+    #define USE_DISPLAY                 
+    #define USE_DISPLAY_MAX7219_MATRIX
+    #define USE_UTF8_LATIN1             // optional. It defines additionaly UTF8_C2 and UTF8_C3 characters and needs +1k more memory.
+    ```
+
 ![20211204_133243](https://user-images.githubusercontent.com/24937182/144709719-2fb4ff2c-7645-4dd8-b0a3-eccd306d63f0.jpg)
 <center><img src="https://user-images.githubusercontent.com/24937182/144709723-833ff002-ef84-431a-b05f-8b7ef30e0072.jpg" width="500"  border="10" /></center>
 
-## Compile and build firmware
-To use this driver, tasmota has to be [compiled](Compile-your-build) with:
-``` C
-#define USE_DISPLAY
-#define USE_DISPLAY_MAX7219_MATRIX
-#define USE_UTF8_LATIN1
-```
-The `#define USE_UTF8_LATIN1` is optional. It defines additionaly UTF8_C2 and UTF8_C3 characters and needs +1k more memory.
-
 ## Wiring
 Connect the [MAX7219](https://www.openimpulse.com/blog/wp-content/uploads/wpsc/downloadables/MAX7219-Datasheet.pdf) [display module's](https://www.handsontec.com/dataspecs/module/MAX7219-4-In-1.pdf) pins to any free GPIOs of the ESP8266 or ESP32 module.
 VCC should be 5V. Depending on the number of used modules and the brightness, the used current could be more than 1A. A seperate 5V adapter connected to the display directly could be helpfull.
@@ -63,10 +64,10 @@ Now, the following "Display" commands can be used:
 | DisplayScrollDelay| [0..15]             | default = 0. Sets the speed of text scroll. Smaller delay = faster scrolling. The maximum scroll speed is 50ms per pixel with ``DisplayScrollDelay 0``.|
 | DisplayWidth  | [8..256]                | Sets the pixel width of the display (8x number of modules in a row) |
 | DisplayHeight | [8..256]                | Sets the pixel height of the display (8x number of module rows) |
-| DisplayRotate | [0/2]                   | 0: default (whwn first module is left), 2 upside down (turns 180°, when first module is right)
+| DisplayRotate | [0/2]                   | 0: default (when first module is left), 2 upside down (turns 180°, when first module is right)
 | DisplayClock  | [0/1/2]                 | Displays a clock. 1: 12 hr format, 2: 24 hr format, 0: turns clock off
 
-**Note**: The DisplayClock mode is not persistent. After a restart it has to be set again or use the following rule to have clock mode permanently.
+**Note**: The DisplayClock mode is not persistent. After a restart it has to be set again manually or use the following rule to have clock mode permanently.
 ```
 rule1 on system#boot do DisplayClock 2 endon
 rule1 1