Update last modified date
Remove redundant footer
Update description of 'orange label' as 'black row' in legend
Add group of radio buttons to select an AR, or all
Give more prominence to top row: larger, more contrast
Extract total for each AR, remove AR level from the treemap

I also prepared the filtering according to selected AR.
Refresh treemap layout when AR selection changes
Configure different durations depending on the transition

A transition one level deep takes now 1s (previously 750ms),
while the transition one level up is twice as fast at 500ms (previously
750ms as well).

The transition on the selection of a different AR is set without
delay to allow a straight comparison over time.