"Humanize" down time info + L10N-lite

Currently for a longer downtime the UI says e.g.
"3,596 s Total Downtime Duration"
as in Europe and Brasil the comma is the decimal separator, people think of three and a half seconds.

Ideally we should format this according to the browser locale to show a . as separator, as this is the 1000s separator.

But we should also make the duration human readable as in HAWKULAR-397 to show 60 mins in above case and not a huge number of seconds. I can imagine that this switch to mins from seconds should kick in with something above 5mins.