Check en (English) locale and fix typos

Check locales by native and fix typos.

Project use [jekyll-multiple-languages-plugin](https://github.com/kurtsson/jekyll-multiple-languages-plugin). Each locale file are keeped in `_18n` folder.
For example `en` is located in `_18n/en.yml` file.

Project was translated by translation service not by human. So it can keep typos.

Need to check current issue language.

- Fork
- Create branch 167_en_locale
- Commit and create PR

Start with the English locale at _18n/en.yml and read the issue's reference to the jekyll-multiple-languages-plugin to understand how locale text is used. Check the current English wording for typos, correct only the language text, and confirm the updated locale remains valid for the project before creating the requested branch and pull request.

Written by the indexing model from the issue text.