title: Set Use value application.properties from another properties
body: <p>I am building a spring boot application, can application.properties value get from another property</p>
  <p>I have an application.properties like this</p>
  <pre><code>spring.datasource.url= jdbc:oracle:thin:@//localhost:1521/test
  org.quartz.dataSource.qDS.URL=jdbc:oracle:thin:@//localhost:1521/ORCL
  </code></pre>
  <p>can Spring boot doing like this ?</p>
  <pre><code>db.connections.url=jdbc:oracle:thin:@//localhost:1521/test
  spring.datasource.url= db.connections.url
  org.quartz.dataSource.qDS.URL=db.connections.url
  </code></pre>