Localize time.Format + time zone support

[bep]

Fixes #8797

[bep]

@regisphilibert @jmooring if we limit the discussion to time.Format (or dateFormat which is the alias).

This function now is:

• Localized
• Supports both Go's special layout syntax and some predefined constants (which I think makes it easier to get multilingual right)

E.g. (more examples in the docs in this PR):

Date: {{ .Date | time.Format ":date_medium" }}

[bep]

@jmooring one question: I have added some improved time zone support to this PR; I have called the new config timeZone because 1) That is what Jekyll uses and I suspect there are many Hugo sites out there already using it and 2) I think it's the term most people understands. Go calls this "time location", which I guess is more precise ... but.

[jmooring]

@bep

I have called the new config timeZone

Good!

Unfortunately most people confuse time zones (e.g., America/Los_Angeles) with time zone abbreviations (e.g., PST) which are essentially useless given the N:N relationship between offsets and time zone abbreviations.

[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.