Add two examples to fs_demo

Author: cristiand391

reference/fs_demo.js

@@ -106,4 +106,15 @@ fs.rmdir(path.join(__dirname, "/myFolderToDelete"), (err) => {
 });
 
 
-
+// Read the contents of a folder
+// NOTE: the first argument can be whatever route you want, it doesn't have to be the actual dirname.
+fs.readdir(__dirname, (err, files) => {
+  if (err) throw err
+  console.log(files)
+}) 
+
+// Copy a file 
+fs.copyFile('source.txt', 'destination.txt', err => {
+  if (err) throw err;
+  console.log('File copied...')
+})