## Issue
Part of `5834 Performance investigation`
In a homepage with 120 tiles, the lists get rendered 3 times during initial update. The sub-components are updating recursively (will investigate), so instead of 120 DateTime renders, we have 1000+ renders.
The resolved DateTime string for `timeAgo` rarely changes, and even if the string was "a few seconds ago", there's no real need to constantly update it.
## Change
Require a minimum 1-minute delta when deciding whether the component should update. Clients can change this value as needed.
## Test
- [x] Verified `shouldComponentUpdate` doesn't end up taking more time than not having it (it's in micro-second range, compared to the millisecond render).
- [x] Profiler showed no significant improvement for low number of DateTime components, but for the 120 DateTime case, almost 1/4 of a second is saved.
The class was only returning a localized string for 'years' and 'months'; English was used for the rest.
- Fixed by handling the remaining cases.
- New strings were added (1) so that they will all be consistent language-wise until the translators handle them all (2) allows for cleaner code through variable re-use (%duration%).
