Add time range info to all items on dashboard

I like to suggest a small improvement to the dashboard.

While it clearly states what time range is used for "Total queries over" and "Client activity" (namely "over the last 24h")

Bildschirmfoto zu 2020-04-17 11-18-52

this information is missing for the other items/sections on the dashboard.

While one can assume/guess it is also 24h (what it is in default) it would be nice if it would be written there. I suggest to change the wording "Top Permitted Domains" to "Top Permitted Domains over last 24h", etc...