Fix i18n issues

[pedro-mendonca]

Description of the Change

• Fix wrong textdomains
• Add missing textdomains
• Add missing comment to translators in string with placeholder
• Fix some simple coding standard issues

Please see issue #294 for a full issue description and screenshots.

Closes #294

How to test the Change

Install a language that the plugin is 100% translated
Go to Settings > Discussion and see all the plugin related strings translated.

Changelog Entry

Fixed - I18n issues

Credits

Props @pedro-mendonca

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.

[dkotter]

@pedro-mendonca Thanks for the PR, this looks and tests great!

[faisal-alvi]

@dkotter We've removed the text domain from avatar_ratings in #175 to fix issues #88 and #157. This PR adds them back, so we should've verified that it doesn't cause the issues to reoccur.

[pedro-mendonca]

@faisal-alvi if the site language is set to Language A, and user-language is set to Language B, all these strings are presented in Language B.
The strings appear in the translation table on w.org, so they should be loaded from the .po file and not from core.

[dkotter]

@dkotter We've removed the text domain from avatar_ratings in #175 to fix issues #88 and #157. This PR adds them back, so we should've verified that it doesn't cause the issues to reoccur.

That's a good callout and is something I tested. I see the proper translations both if a site language is set and if a user language is set when testing this PR. Not sure if there are other changes we've made that helped fix this since the original issue was reported but I'm not seeing any regression, though feel free to test yourself to ensure that is the case