update support typescript

Author: ThaiVH

package.json

@@ -3,6 +3,7 @@
   "version": "2.1.0",
   "description": "Charset Detector - Detect the encoding and language of text files - Use it in the browser, with Node.js, or via CLI",
   "main": "src/index-node.js",
+  "types": "src/index-node.d.ts",
   "scripts": {
     "regextest": "node ./testing/regexTester.test.js",
     "test": "node ./testing/language-encoding.test.js",

src/index-node.d.ts

@@ -0,0 +1,11 @@
+export interface FileInfo {
+    encoding: null | string,
+    language: null | string,
+    confidence: {
+        encoding: null | string,
+        language: null | string,
+    },
+}
+
+declare function DetectFileEncodingAndLanguage(file: File): Promise<FileInfo>
+export default DetectFileEncodingAndLanguage;