Add types declaration file (#4)

* Add types declaration file

* Add TS info to Readme, amend declaration file

README.md

@@ -63,7 +63,7 @@ import "text-terminal/dist/text-terminal.css";
 const commands = {};
 
 const config = {
-  containerId = "text-terminal",
+  containerId: "text-terminal",
   prompt: "textTerm@quest",
   theme: "dark",
   commands: commands,
@@ -72,6 +72,22 @@ const config = {
 const terminal = new TextTerminal(config);
 ```
 
+Text Terminal also comes with TypeScript compatibility out of the box, so you can use it in your TypeScript projects. To adapt from the above excerpt:
+
+```typescript
+// Create a new TextTerminal with a config object where all properties are optional
+const terminal = new TextTerminal({
+  containerId: "text-terminal",
+  prompt: "textTerm@quest",
+  theme: "dark",
+  commands: {},
+});
+
+// All methods of the TextTerminal class are recognised by your IDE with correct typing
+terminal.createDom(document.getElementById("my-element")); // HTMLElement argument type
+terminal.output("Hey Text Terminal!") // string argument type
+```
+
 ## Themes
 
 Text Terminal has the following themes bundled with it:

dist/text-terminal.d.ts

@@ -0,0 +1,34 @@
+declare module "text-terminal" {
+  export default class TextTerminal {
+    constructor(options?: Partial<{
+      containerId: string;
+      commands: object;
+      prompt: string;
+      theme: string;
+      welcome: string;
+      separator: string;
+    }>);
+
+    addListeners(): void;
+
+    /**
+     * Clears the contents of the terminal output.
+     */
+    clear(): void;
+
+    /**
+     * Outputs the version of Text Terminal.
+     */
+    version(): void;
+
+    createDom(containerEl: HTMLElement): void;
+
+    onKeyDown: (event: Event) => void;
+
+    onKeyUp: (event: Event) => void;
+
+    output(command: string): void;
+
+    resetCommand: () => void;
+  }
+}

package.json

@@ -11,6 +11,7 @@
     "lint-fix": "prettier --write ."
   },
   "main": "dist/text-terminal.js",
+  "types": "dist/text-terminal.d.ts",
   "author": "Des Holmes https://github.com/desholmes",
   "license": "MIT",
   "devDependencies": {