Add and improve I18n for application templates

[buren]

I finally got around replacing/updating #785, which adds better I18n support for administrate.

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• Removes "hardcoded" placement of resource name for edit/new/show links (problematic on Arabic and other right-to-left languages since the positioning of the name will be flipped too).
• Update config/locale/administrate.en.yml
• Includes the latest commit from master
• Use display_resource_name consistently when calling page.resource_name in view templates
• Update all other locale files
  • Any comments/suggestions on how I best should go about this?
  • If I use i18n-tasks add-missing other updates (formatting etc) are made in the locale files
  • Should we try to re-use the existing strings or do we deem that dangerous and think its better that translations are re-done by someone who actually understands the language? 😅

⚠️ There is one expected test failure for rspec ./spec/i18n_spec.rb:9 # I18n does not have missing keys (see TODO)

[hanneskaeufler]

I improved the german translation in a similar pr. See #1002. To preserve the existing behaviour for all other locales I reused the existing translation and tackes on the resource token. But surely this is not optimal for many more locales other then german as well.

[buren]

tl;dr Updated locales, tests are passing 🎉

I've updated non-default locales now I ended up including most of the locale changes @hanneskaeufler did in #1002. Thanks for that! Saved me a lot of time my editor didn't play nice with the arabic strings :)

@hanneskaeufler I didn't include your German translation update (keys: search.label, search.clear). Thought that would be better to put in a separate PR.

@nickcharlton let me know if there are any changes you want and if I should squash all the commits together as one :)

[nickcharlton]

Hi @buren!

This is looking good to me. I like the way the commits are split up, so I'm not going to squash them here.

What do you think about me merging #1002, then you rebasing on top of that? It'll solve the separate PR issue you mention (I think?).

[buren]

@nickcharlton perhaps merging this and then just opening a new PR with just the 2-line German fix? If @hanneskaeufler is unavailable to do it, I can :) Then the I18n fix for German would be as clean as possibly can be.

[hanneskaeufler]

Sure go ahead and merge this and I'll update/reopen something similar to #1002.

[buren]

@nickcharlton something blocking this? :)

Can I do anything to help?

[nickcharlton]

@buren Just my time to hit the magic button!

I'm going to merge this now. Thanks for all of your time on it!

@hanneskaeufler if you could go ahead and do the German language fix in a new PR, that'd be wonderful.

[buren]

@nickcharlton 🎉 Sweat!

Thank you!