Added README

Author: jasonjoh

README.md

@@ -0,0 +1,55 @@
+# Getting Started with the Outlook Mail API and Node.js #
+
+This sample app is the result of following the tutorial at [https://docs.microsoft.com/en-us/outlook/rest/node-tutorial](https://docs.microsoft.com/en-us/outlook/rest/node-tutorial). If you follow that tutorial, you should come up with something fairly close to the code in this repository.
+
+> **NOTE:** Looking for the version of this tutorial that used the Outlook API directly instead of Microsoft Graph? Check out the `outlook-api` branch. Note that Microsoft recommends using the Microsoft Graph to access mail, calendar, and contacts. You should use the Outlook APIs directly (via https://outlook.office.com/api) only if you require a feature that is not available on the Graph endpoints.
+
+## Prerequisites
+
+- Node.js installed and working on your development machine. 
+- An Office 365 tenant, with access to an administrator account in that tenant, **OR** an Outlook.com account.
+
+## Running the sample
+
+If you didn't follow the tutorial and just want to download this repo and try it out, you need to do a few things first.
+
+## Register the app
+
+Before we proceed, we need to register our app to obtain a client ID and secret. Head over to https://apps.dev.microsoft.com to quickly get a client ID and secret. Using the sign in buttons, sign in with either your Microsoft account (Outlook.com), or your work or school account (Office 365).
+
+Once you're signed in, click the **Add an app** button. Enter `node-tutorial` for the name and click **Create application**. After the app is created, locate the **Application Secrets** section, and click the **Generate New Password** button. Copy the password now and save it to a safe place. Once you've copied the password, click **Ok**.
+
+![The new password dialog.](readme-images/new-password.PNG)
+
+Locate the **Platforms** section, and click **Add Platform**. Choose **Web**, then enter `http://localhost:3000/authorize` under **Redirect URIs**. Click **Save** to complete the registration. Copy the **Application Id** and save it along with the password you copied earlier. We'll need those values soon.
+
+Here's what the details of your app registration should look like when you are done.
+
+![The completed registration properties.](readme-images/node-tutorial.PNG)
+
+## Configure the sample
+
+Rename the `sample.env` file to `.env`. Replace the `YOUR APP ID HERE` with the application ID and `YOUR APP PASSWORD HERE` with the password you generated and save your changes.
+
+Open your command prompt or shell and enter the following command to install dependencies.
+
+```Shell
+npm install
+```
+
+## Run the sample
+
+Open your command prompt or shell and enter the following command.
+
+```Shell
+npm start
+```
+
+## Copyright ##
+
+Copyright (c) Microsoft. All rights reserved.
+
+----------
+Connect with me on Twitter [@JasonJohMSFT](https://twitter.com/JasonJohMSFT)
+
+Follow the [Outlook/Exchange Dev Blog](https://blogs.msdn.microsoft.com/exchangedev/)