Make select changelog entries translatable

[Hans5958]

Based on #297 (comment), I'm exploring the idea whether to translate the changelog. For now, the most logical option is to translate just the highlights (also the name but it is unset currently), as it is based on the update notifications on the extension, which has been translated.

This would require that translators redo these translations. I have made https://github.com/ScratchAddons/notification-to-highlights so translators can copy the translated strings, and maybe do a little bit adjustment if necessary, if it is translated at the time of the version, that is.

TODO

• Create i18n scripts for the changelog
  • English to i18n
  • i18n to English
• Complete all versions of notification-to-highlights
• Attempt translating using old strings with code
• Do some tests
• Push all strings on Transifex
• Announce on Transifex regarding the changes

[Hans5958]

Some reasons regarding why translators needing to copy the strings.

1. Creating a tool to generate translations may not worth the initial cost (up for grabs, if anyone wants)
2. Differing formats may introduce issues
3. Giving a chance for translators to check and fix issues on existing translation

PS. I actually have an idea by trial-and-error by using the English strings and attempt replacing it with the translated strings. This can be explored. Hopefully uploading it would be easy...

[Hans5958]

I have attempted to translate the highlights using the old script. It's my best attempt so it may need to be checked for errors.

Example: https://github.com/ScratchAddons/website-i18n/blob/12714b1268cf8fc67d7cf641feafbb0cb0d68457/es/changelog.yml

• The code can be seen on https://github.com/ScratchAddons/website-v2-script/tree/changelog-i18n
• The strings, including the translation using old string (at least an the attenpt) can be seen on https://github.com/ScratchAddons/website-i18n/tree/changelog