title: JHipster - replace default template with a new angular template
body: <p>I have a project generated with jHipster-generator , it's a microservice gateway, and I'm using an angular template called "Gradient Able" (<a href="http://html.codedthemes.com/gradient-able/angular-5/default/dashboard/default" rel="nofollow noreferrer">http://html.codedthemes.com/gradient-able/angular-5/default/dashboard/default</a>). </p>
  
  <p>I'm new to Angular , So my question is  : </p>
  
  <ul>
  <li>What is the best way to integrate the template inside the default 
   jHipster generated angular source ?</li>
  <li>Also is there a way to adapt the future generation of entities to the 
   new template design or I should change every time the component generated ?</li>
  </ul>
  
  <p>Bellow the default template structure : </p>
  
  <p><a href="https://i.stack.imgur.com/jlDCY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jlDCY.png" alt="enter image description here"></a></p>