Add chinese translation

_locales/zh/messages.json

@@ -0,0 +1,29 @@
+{
+    "extensionLocale": {
+        "message": "en",
+        "description": "Used to check which locale is loaded, as it might be different from @@ui_locale."
+    },
+    "extensionName": {
+        "message": "Talkie"
+    },
+    "extensionShortName": {
+        "message": "Talkie"
+    },
+    "extensionDescription": {
+        "message": "在任何网页上选择文字，并让计算机大声读出它，只需点击对讲机按钮。"
+    },
+    "buttonDefaultTitle": {
+        "message": "大声读出文本选择"
+    },
+    "noTextSelectedMessage": {
+        "message": "请先在网站上选择所需的文字！"
+    },
+    "noVoiceForLanguageDetectedMessage": {
+        "message": "Sorry, no available voice language detected for the selected text.",
+        "description": "This is a fallback message. For this reason it is always in English."
+    },
+    "noVoiceForLanguageDetectedMessageLanguage": {
+        "message": "en",
+        "description": "This is a fallback message. For this reason it is always in English."
+    }
+}