config.txt: move i18n.* to a separate file

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/config.txt

@@ -351,16 +351,7 @@ include::config/help.txt[]
 
 include::config/http.txt[]
 
-i18n.commitEncoding::
-	Character encoding the commit messages are stored in; Git itself
-	does not care per se, but this information is necessary e.g. when
-	importing commits from emails or in the gitk graphical history
-	browser (and possibly at other places in the future or in other
-	porcelains). See e.g. linkgit:git-mailinfo[1]. Defaults to 'utf-8'.
-
-i18n.logOutputEncoding::
-	Character encoding the commit messages are converted to when
-	running 'git log' and friends.
+include::config/i18n.txt[]
 
 imap::
 	The configuration variables in the 'imap' section are described

Documentation/config/i18n.txt

@@ -0,0 +1,10 @@
+i18n.commitEncoding::
+	Character encoding the commit messages are stored in; Git itself
+	does not care per se, but this information is necessary e.g. when
+	importing commits from emails or in the gitk graphical history
+	browser (and possibly at other places in the future or in other
+	porcelains). See e.g. linkgit:git-mailinfo[1]. Defaults to 'utf-8'.
+
+i18n.logOutputEncoding::
+	Character encoding the commit messages are converted to when
+	running 'git log' and friends.