Enable user to choose time granularity from filter slice

[AxelDelmas]

Filter slices are very useful to apply filters to all slices of a dashboard.
Time filters already enable to set from and to parameters, but there is currently no possibility to change the time granularity.
It would be very useful to add that option as well, as the only way for now is to explore each graph individually (which defeats the purpose of dashboards)

[mistercrunch]

Notice: this issue has been closed because it has been inactive for 508 days. Feel free to comment and request for this issue to be reopened.