Add index.d.ts file to distribution

Author: blakeembrey

index.d.ts

@@ -0,0 +1,16 @@
+declare function numbered (input: string): number;
+declare function numbered (input: number): string;
+
+declare namespace numbered {
+  /**
+   * Transform a number string into a number.
+   */
+  export function parse (input: string): number;
+
+  /**
+   * Transform a number into the string representation.
+   */
+  export function stringify (input: number): string;
+}
+
+export = numbered;

package.json

@@ -1,8 +1,13 @@
 {
   "name": "numbered",
   "version": "1.0.0",
-  "description": "Turns a number into word based equivalent, and parse it back again",
+  "description": "Stringify any number into words, and parse number strings back to a number",
   "main": "index.js",
+  "typings": "index.d.ts",
+  "files": [
+    "index.js",
+    "index.d.ts"
+  ],
   "scripts": {
     "test": "istanbul cover _mocha -- -R spec"
   },