Bug#933608: Say in Description if one should use this package or the Chrome Web Store version

[積丹尼 Dan Jacobson]

OK, but the user wonders "maybe the two sources aren't even aware of
each other, that's why they are duplicating their work."

And "Odd, some items in the Chrome Web Store are also available as
Debian packages. Why the fuss?"

All items for an FAQ.

Anyway, I suppose the Chrome Web Store version will always be newer or
equal to the Debian version.