* enabled mermaid by default
* implemented logic to use internal oder cdn mermaid
* added english documentation
* added french translation for the mermaid options
* Removed useless test print
* Hugo does not use upper case letters in params
* fixed false sample link
* improved mermaid pages
* fixed always load mermaid if no frontmatter specified
* fixed mermaid samples
* removed obsolete css files
* changed default version of mermaid cdn
* renamed mermaidURL to customMermaidURL and removed css link
* improved mermaid configuration description
Co-authored-by: Arthur Ferdinand Lindner <Arthur-Ferdinand.Lindner@Telekom.de>
Co-authored-by: Arthur Ferdinand Lindner <arthur.lindner@outlook.de>
Previously adding custom css files would require the end user to copy
the header or footer partial into their overrides. They would then
need to maintain that partial into the future.
This config allows a user to provide a list of custom css files to load
into the theme, meaning they do not need to clone the partial.
```
[params]
custom_css = ["css/foo.css", "css/bar.css"]
```
Inspiration taken from https://discourse.gohugo.io/t/how-to-override-css-classes-with-hugo/3033/4
