Compatibility with org.springframework.web.servlet.view.ContentNegotiatingViewResolver

This pull request has been made to be able to chain the ViewResolvers (as previously intended by Spring).

The pull request includes:
- A overridden method *checkResource()* returning false when no template is attached to the view.
- A test case for avoiding regressions.

Tested on an application using both the Mustache templating and Freemarker templating. Works fine. The development follows the *FreemarkerViewResolver*.