[Features] Content list and add a download 'view source' link or button

[Tuxman2]

Hello,

I propose two interesting new features. First, the content list which allows you to switch automatically between sections in the same page (see Sphinx Book Theme -> Content section in the right upper corner in the main page of this theme).

Second, A button or link allowing you to download the view source code (see Sphinx Book Theme).

I don't know if there is a way to print or download the whole documents in pdf or epub files throught the interface of the theme without using the terminal and the command lines under sphinx (for example : make latexpdf).

Thanks.

Regards.