This makes the UI cleaner...
Overview itself got cleaner and we could remove the "more details" link and just always show all sparklines.
The two reports below the overview were moved into "All Referrers" containing a report "Referrer Types" and "Referrers". I removed the "By dimension view" as it was only duplicated anyway. In "Referrers" all columns are now shown by default so that both reports have the same width. Names of the titles could be changed later. "Referrer Type" was often or always used elsewhere so I reused that naming.
After merging we need to update translations, fix UI tests and add a UI test for "all referrers"
FYI: I updated oTrance