Use ISO 8601 dates in Portfile comments

Mon Apr 8 05:42:09 UTC 2019

On Mon, 8 Apr 2019 at 07:35, Joshua Root wrote:
>
> ISO 8601 is a great compliant solution to recommend.
>
> Changing ambiguous dates to something unambiguous is a reasonable thing
> to submit PRs for if you so desire.

Ambiguous dates can be verified with "git log".

But I would do a PR for everything anyway (and merge it after three
days as nobody would complain :)

Mojca