Add installation link (#762)

README.md

@@ -38,8 +38,9 @@ A big thank you to all my beer sponsors for their donations and encouragements.
 
 The documentation is now divided into several pages for easier reading and searching:
 1. [Introduction](documentation/en/presentation.md),
-2. [Choosing a VTherm type](documentation/en/creation.md),
-3. [Basic attributes](documentation/en/base-attributes.md)
+2. [Installation](documentation/en/installation.md),
+3. [Choosing a VTherm type](documentation/en/creation.md),
+4. [Basic attributes](documentation/en/base-attributes.md)
 3. [Configuring a VTherm on a `switch`](documentation/en/over-switch.md)
 3. [Configuring a VTherm on a `climate`](documentation/en/over-climate.md)
 3. [Configuring a VTherm on a valve](documentation/en/over-valve.md)
@@ -103,4 +104,4 @@ If you wish to contribute, please read the [contribution guidelines](CONTRIBUTIN
 [license-shield]: https://img.shields.io/github/license/jmcollin78/versatile_thermostat.svg?style=for-the-badge
 [maintenance-shield]: https://img.shields.io/badge/maintainer-Joakim%20Sørensen%20%40ludeeus-blue.svg?style=for-the-badge
 [releases-shield]: https://img.shields.io/github/release/jmcollin78/versatile_thermostat.svg?style=for-the-badge
-[releases]: https://github.com/jmcollin78/versatile_thermostat/releases
+[releases]: https://github.com/jmcollin78/versatile_thermostat/releases