Fix RST links for PlatformIO (#7143)

* Fix RST links

* Update links to PlatformIO

Author: ivankravets

README.md

@@ -48,19 +48,19 @@ Also known as latest git or master branch.
 
 ### Using PlatformIO
 
-[PlatformIO](https://platformio.org?utm_source=github&utm_medium=arduino-esp8266) is an open source ecosystem for IoT
+[PlatformIO](https://platformio.org?utm_source=arduino-esp8266) is an open source ecosystem for IoT
 development with a cross-platform build system, a library manager, and full support
 for Espressif (ESP8266) development. It works on the following popular host operating systems: macOS, Windows,
 Linux 32/64, and Linux ARM (like Raspberry Pi, BeagleBone, CubieBoard).
 
-- [What is PlatformIO?](https://docs.platformio.org/en/latest/what-is-platformio.html?utm_source=github&utm_medium=arduino-esp8266)
-- [PlatformIO IDE](https://platformio.org/platformio-ide?utm_source=github&utm_medium=arduino-esp8266)
-- [PlatformIO Core](https://docs.platformio.org/en/latest/core.html?utm_source=github&utm_medium=arduino-esp8266) (command line tool)
-- [Advanced usage](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=github&utm_medium=arduino-esp8266) -
+- [What is PlatformIO?](https://docs.platformio.org/en/latest/what-is-platformio.html?utm_source=arduino-esp8266)
+- [PlatformIO IDE](https://platformio.org/platformio-ide?utm_source=arduino-esp8266)
+- [PlatformIO Core](https://docs.platformio.org/en/latest/core.html?utm_source=arduino-esp8266) (command line tool)
+- [Advanced usage](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=arduino-esp8266) -
   custom settings, uploading to SPIFFS, Over-the-Air (OTA), staging version
-- [Integration with Cloud and Standalone IDEs](https://docs.platformio.org/en/latest/ide.html?utm_source=github&utm_medium=arduino-esp8266) -
+- [Integration with Cloud and Standalone IDEs](https://docs.platformio.org/en/latest/ide.html?utm_source=arduino-esp8266) -
   Cloud9, Codeanywhere, Eclipse Che (Codenvy), Atom, CLion, Eclipse, Emacs, NetBeans, Qt Creator, Sublime Text, VIM, Visual Studio, and VSCode
-- [Project Examples](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=github&utm_medium=arduino-esp8266#examples)
+- [Project Examples](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=arduino-esp8266#examples)
 
 ### Building with make
 

doc/installing.rst

@@ -234,16 +234,16 @@ Instructions - Other OS
 Using PlatformIO
 ----------------
 
-[PlatformIO](https://platformio.org?utm_source=github&utm_medium=arduino-esp8266) is an open source ecosystem for IoT
-development with a cross-platform build system, a library manager, and full support
-for Espressif (ESP8266) development. It works on the following popular host operating systems: macOS, Windows,
-Linux 32/64, and Linux ARM (like Raspberry Pi, BeagleBone, CubieBoard).
-
-- [What is PlatformIO?](https://docs.platformio.org/en/latest/what-is-platformio.html?utm_source=github&utm_medium=arduino-esp8266)
-- [PlatformIO IDE](https://platformio.org/platformio-ide?utm_source=github&utm_medium=arduino-esp8266)
-- [PlatformIO Core](https://docs.platformio.org/en/latest/core.html?utm_source=github&utm_medium=arduino-esp8266) (command line tool)
-- [Advanced usage](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=github&utm_medium=arduino-esp8266) -
-  custom settings, uploading to SPIFFS, Over-the-Air (OTA), staging version
-- [Integration with Cloud and Standalone IDEs](https://docs.platformio.org/en/latest/ide.html?utm_source=github&utm_medium=arduino-esp8266) -
-  Cloud9, Codeanywhere, Eclipse Che (Codenvy), Atom, CLion, Eclipse, Emacs, NetBeans, Qt Creator, Sublime Text, VIM, Visual Studio, and VSCode
-- [Project Examples](https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=github&utm_medium=arduino-esp8266#examples)
+`PlatformIO <https://platformio.org?utm_source=arduino-esp8266>`__
+is an open source ecosystem for IoT development with a cross-platform
+build system, a library manager, and full support for Espressif
+(ESP8266) development. It works on the following popular host operating
+systems: macOS, Windows, Linux 32/64, and Linux ARM (like Raspberry Pi,
+BeagleBone, CubieBoard).
+
+- `What is PlatformIO? <https://docs.platformio.org/en/latest/what-is-platformio.html?utm_source=arduino-esp8266>`__
+- `PlatformIO IDE <https://platformio.org/platformio-ide?utm_source=arduino-esp8266>`__
+- `PlatformIO Core <https://docs.platformio.org/en/latest/core.html?utm_source=arduino-esp8266>`__ (command line tool)
+- `Advanced usage <https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=arduino-esp8266>`__ - custom settings, uploading to SPIFFS, Over-the-Air (OTA), staging version
+- `Integration with Cloud and Standalone IDEs <https://docs.platformio.org/en/latest/ide.html?utm_source=arduino-esp8266>`__ - Cloud9, Codeanywhere, Eclipse Che (Codenvy), Atom, CLion, Eclipse, Emacs, NetBeans, Qt Creator, Sublime Text, VIM, Visual Studio, and VSCode
+- `Project Examples <https://docs.platformio.org/en/latest/platforms/espressif8266.html?utm_source=arduino-esp8266#examples>`__