Add language percentages to classic template

[Nixinova]

It would be useful to have something like this available for use in the classic template:

The percentages are already in the terminal template and it would be good to have the percentages available in classic as well.

[lowlighter]

Added with #87 👍

[Nixinova]

Will this option be available on the web instance as well?

[lowlighter]

Yes it's available on shared web instance since it does not consume too much query 🙂

[Nixinova]

The URL query parameter works, but the config option doesn't show up in the list.

[lowlighter]

It's there but I confess param name isn't very clear.
Placeholder binding may be broken, I'll take a look at it