Add time frame as URL parameter

[blacktemplar]

Adding the selected time frame as URL parameter has multiple advantages:

1. Time frame gets remembered when refreshing the page
2. One can share links for a specific time frame

This should of course happen without refreshing the page when changing the time frame, just update the URL. This should be possible technically.

[alextes]

i like this idea. we could have multiple parameters as there are multiple dashboards with time frames. it would work even better when we finally split the page into multiple pages / sections so each page can have its own straightforward time frame parameter.