fix readme

Author: sanv92

README.md

@@ -1,6 +1,12 @@
 # Exceptions
 
 ### Install
+
+#### Create file .npmrc
+```
+echo "@awesome-typescript:registry=https://npm.pkg.github.com" > .npmrc
+```
+#### Install npm package
 ```
 npm install [email protected] --save --save-exactcl
 ```