Update requirements docs page
* Development of this library follows latest ESP8266 AT software development by Espressif systems.
*
* - ESP8266 must include latest AT software
- * - Currently supported AT version is <b>1.6.0</b> based on SDK version `2.2.0` which is not yet officially released by EspressIf Systems
+ * - Currently supported AT version is `1.6.0` based on SDK version `2.2.0` which is not yet officially released by EspressIf Systems
* - Precompiled development AT version from Espressif is available on Github of this library: https://github.com/MaJerle/ESP_AT_Lib/tree/master/bin
* - If you are not sure which version is running on ESP, you may test it using `AT+GMR\r\n` command.
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