Enable 'standard' publication types to be rendered

[1pretz1]

Adds locales needed to render the new 'standard' document type.

I've added the foreign translation placeholders as they are used unlike the the ones located in Whitehall. We'll need to decide if we want a translation for all locales, some or just for English.

Dependent on:

• Foreign locale translations being agreed upon and implemented (decision is for no translations to be created initially)

Trello:
https://trello.com/c/ugeapNY0/2318-5-create-new-standard-document-sub-type-in-whitehall

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I've pushed some commits since reviewing

[ChrisBAshton]

LGTM, though I've been a little out of the loop on the i18n standardisation stuff. Is there a reason why the English version only has one and other defined, and all the translations have other (empty) counts which will likely never have values?

[ChrisBAshton]

Can we remove the empty zero/two/few/many properties, like in the English version?

[brucebolt]

The pluralisation rules for Welsh require us to have a zero, two, few and many value. We weren't provided with translations for these, so the empty values should help us identify outstanding translations when we do this piece of work. I've also done the same for other languages that don't have a one-other pluralisation rule (e.g. Croatian).