Resolve "Data visualization: Add Date header"

Date control

As the date input isn't finished yet, I won't close the issue after this merge request. This can still be merged / approved however. I'll add a second MR for when the date input is ready

UX

I wrote a comment on the issue about this, but I'll repeat it here so it doesn't crop up as a review comment - the current UX is somewhat confusing. Currently if you refresh the page, then click on 'Year' - wanting to see the data within one year - you'll in fact only see the data for one week still, as the end date has been set to a year in the future, and you don't have any data for this time span.

Partially fixes #441