Update README.md

Author: pphod

README.md

@@ -4,13 +4,15 @@
 
 Make sure import the CSS and JS classes in your angular.json file
 
+<pre>
 "styles": [
-              ...
-              "./node_modules/jexcel/dist/jexcel.css"
-            ],
-            "scripts": [
-              "./node_modules/jexcel/dist/jexcel.js"
-            ]
+  ...
+  "./node_modules/jexcel/dist/jexcel.css"
+],
+"scripts": [
+  "./node_modules/jexcel/dist/jexcel.js"
+]
+</pre>
 
 ## HTML FILE