title: Remove/add value onfocus/onblur if empty in jquery, input field
body: <p>I know there exists many questions about this, but I dont know what to search.</p>
  
  <p>I have a email field, and I want it to have "Write your email here" and when you click/do onfocus it should disappear. Although if you did not write something and go onblur it should appear again.</p>