Update documentation for nixpkgs breaking change (Riey#669)

nixpkgs change: NixOS/nixpkgs#310708

Author: importantblimp

README.ko.md

@@ -49,7 +49,8 @@
 i18n = {
   defaultLocale = "en_US.UTF-8";
   inputMethod = {
-    enabled = "kime";
+    enable = true;
+    type = "kime";
     kime.config = {
       indicator.icon_color = "White";
     };

README.md

@@ -49,7 +49,8 @@ Add this code to your configuration.nix
 i18n = {
   defaultLocale = "en_US.UTF-8";
   inputMethod = {
-    enabled = "kime";
+    enable = true;
+    type = "kime";
     kime.config = {
       indicator.icon_color = "White";
     };