code: public static ConfigFactory
      webappConfigFactory(ServletContext servletContext) {
  
          checkNotNull(servletContext);
  
          return webappConfigFactory()
              .bind(ServletContextPath.class)
              .toInstance(ServletContextPath.fromServletContext(servletContext));
      }
docs: A sensible default configuration factory for a web application.
  
  <p>Config sources, in order from highest to lowest precedence:</p>
  <ul>
  <li>System properties</li>
  <li>File:
  {@code JNDI(webapp.config.directory)/[servlet context path]}</li>
  <li>File:
  {@code ${webapp.config.directory}/[servlet context path]}</li>
  <li>File: {@code JNDI(webapp.config.file)}</li>
  <li>File: {@code ${webapp.config.file}}</li>
  <li>Classpath resource: {@code application.conf}</li>
  <li>Classpath resource: {@code resource.conf}</li>
  </ul>