docs: Add a contributing docs guide (#2129)

docs/content/contributing/documentation.md

@@ -2,5 +2,52 @@
 title: 'Contributing | Documentation'
 ---
 
-!!! todo
-    This section should provide a detailed step by step guide on how to contribute to documentation
+## Prerequisites
+
+You will need have Python and Python pip installed. Or just docker.
+
+## Building and serving the documentation
+
+This tutorial was written using Python `2.7.18` and Python pip `20.3.4`.
+And Docker `19.03.6`.
+
+### Python way
+
+#### Install the modules
+
+The documentation builder
+
+```sh
+pip install mkdocs
+```
+
+Now the theme
+
+```sh
+pip install mkdocs-material
+```
+
+#### Serve
+
+!!! note "Note: be sure to be in the docs folder (`cd ./docs/`)"
+
+```sh
+mkdocs serve
+```
+
+Wait for it to build and open the URL in your browser.
+Each change will be hot-reloaded onto the page you view, just edit, save and look at the result.
+
+### Docker way
+
+Using the official image ([squidfunk/mkdocs-material](https://hub.docker.com/r/squidfunk/mkdocs-material)) for our documentation theme.
+
+#### Serve
+
+!!! note "Note: be sure to be in the docs folder (`cd ./docs/`)"
+
+```sh
+docker run --rm -it -p 8000:8000 -v ${PWD}:/docs squidfunk/mkdocs-material
+```
+
+Each change will be hot-reloaded onto the page you view, just edit, save and look at the result.