refactor: migrate i18n files from YAML to TOML format and simplify structure (#1230)

* refactor: migrate i18n files from YAML to TOML format and simplify structure

* refactor: make translation file adjust to gohugoio/locales language code so date translation can work properly

* refactor: use hyphens instead of underscores for i18n, because that's how Hugo pick the translation file

* docs: update comments for i18n language availability and CJK language detection in hugo.toml.

i18n/bg.toml

@@ -0,0 +1,47 @@
+toggleMenu = "Покажи Меню"
+darkMode   = "Тъмен Режим"
+
+[list]
+    section = "Секция"
+
+    [list.page]
+        one   = "{{ .Count }} страница"
+        other = "{{ .Count }} страници"
+
+    [list.subsection]
+        one   = "Подсекция"
+        other = "Подсекции"
+
+[article]
+    back            = "Назад"
+    tableOfContents = "Съдържание"
+    relatedContent  = "Свързано Съдържание"
+    lastUpdatedOn   = "Последна промяна на"
+
+    [article.readingTime]
+        one   = "{{ .Count }} minute read"
+        other = "{{ .Count }} minute read"
+
+[notFound]
+    title    = "Не е намерено"
+    subtitle = "Страницата която търсите не е открита"
+
+[widget]
+    [widget.archives]
+        title = "Архиви"
+        more  = "Повече"
+
+    [widget.tagCloud]
+        title = "Тагове"
+
+    [widget.categoriesCloud]
+        title = "Категории"
+
+[search]
+    title       = "Търсене"
+    placeholder = "Напишете нещо..."
+    resultTitle = "#PAGES_COUNT страници (#TIME_SECONDS секунди)"
+
+[footer]
+    builtWith  = "Създадено с {{ .Generator }}"
+    designedBy = "Тема {{ .Theme }} създадена от {{ .DesignedBy }}"