Add support for --destination in config.json

[N6REJ]

Is your feature request related to a problem? Please describe.
Gitlab requires pages to be in the "public" folder.

Describe the solution you'd like
"html": {
"destination_folder": "../public"
}

having to use --destination="../public" each time is highly annoying.

[onigoetz]

Hello, I'll have a look at this. But can't promise any release date.

[onigoetz]

I'm coming back to this.
I wanted to implement it and wondered : if you set a relative path in this configuration. should it apply it relative to the configuration file, the root of the docs folder or the current working directory ?

I'm not entirely sure which is the most intuitive

[N6REJ]

I'd say relative to root of docs. Just make sure it accepts ../ as a valid path.