Display dates in the user's time zone

[eloquence]

Currently we display dates like "3 Apr" based on the last_updated date on the server. That timestamp is updated in various places, e.g. here, using UTC time. This means that a user may see dates that appear to be in the future.

In the client, we should convert the date to the timezone configured in sd-app (which will reflect whatever timezone is configured with timedatectl in dom0 after a VM restart).

[zenmonkeykstop]

Worth doing, some things to consider:

• should support l10nized datetime formats (see #1536)
• should look at whether we can drop arrow module currently formatting times (may be in conflict with above.

[eloquence]

Milestoning for now for 1.0.0 (rewrite); i18n is in some ways harder to bolt on later (UX choices have to be revisited etc.), so it'd be good to address as part of an i18n baseline similar to the performance baseline goal.

[cfm]

Done in #2658.