removed nodemon.json and changed readme

Author: Maximilian Schwarzmüller

README.MD

@@ -3,3 +3,13 @@ This repository accompanies my YouTube video series on building a RESTful API wi
 
 ## Usage
 Check out the branch you're interested in (i.e. which belongs to the video in my series you just watched), ```git clone``` it and thereafter run ```npm install```.
+
+Make sure to also add your Mongo Atlas Admin Username to a nodemon.json file (which you have to create).
+
+```
+{
+    "env": {
+        "MONGO_ATLAS_PW": "YOUR_MONGO_USER_PW"
+    }
+}
+```