support i18n tagline and title

config/_default/languages.toml

@@ -2,8 +2,14 @@
   languageName = "English"
   languageCode = "en"
   weight = 2
+  title = "Chirpy"
+  [en.params]
+    tagline = "A text-focused blog theme"
 
 [zh-CN]
   languageName = "中文"
   languageCode = "zh-CN"
   weight = 1
+  title = "Chirpy"
+  [zh-CN.params]
+    tagline = "一个专注于文本的博客主题"

config/_default/params.toml

@@ -1,7 +1,6 @@
 theme_version = "5.2.0"
 toc = true
 avatar = "img/commons/avatar.jpg"
-tagline = "A text-focused Jekyll theme"
 
 [assets]
   self_host = false