title: spring autoconfiguration class is missing in META-INF/spring.factories
body: <p>I'm trying to create spring based application but after the build i'm getting exception while initializing the spring context -> <code>No auto configuration classes found in META-INF/spring.factories</code>.
  I'm working heavily with spark in my application and i'm forced to use <code>maven-assembly-plugin</code> to package my jar (otherwise i'm unable to run spark job).</p>
  
  <p>sample of my main class:</p>
  
  <pre><code>@SpringBootApplication
  @EnableAutoConfiguration
  public class MyMainClass {
      public static void main(String[] args) {
  
          ConfigurableApplicationContext ctx = new SpringApplicationBuilder(MyMainClass.class).web(false)
                                                                                                     .run(args);
          SparkJob job = ctx.getBean(SparkJob.class);
          job.prepareJobAndRun();
          ctx.close();
      }
  }
  </code></pre>
  
  <p>when i add </p>
  
  <pre><code>org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
  org.mypackage.MyMainClass
  </code></pre>
  
  <p>everything works as expected, but i don't want to add them manually.
  Any chance to make this work without the <code>spring-boot-maven-plugin</code>?</p>