title: Search and Replace File and Folder name
body: <p>I have the following file structure :</p>
  
  <pre><code>.
  ├── data
  │   └── test_sample.txt
  └── demo_test
      ├── data.php
      ├── index_test.php
      └── Test.php
  </code></pre>
  
  <p>I want to replace 'test' with 'demo'. The final file structure will be</p>
  
  <pre><code>.
  ├── data
  │   └── demo_sample.txt
  └── demo_demo
      ├── data.php
      ├── index_demo.php
      └── Test.php
  </code></pre>
  
  <p>How can I achieve this via a shell script.</p>
  
  <p>Thanks in Advance.</p>