Expand static resource handling mechanism

An initial commit with expanded support for static resource handling:

- Add ResourceResolver strategy for resolving a request to a Resource
  along with a few implementations.

- Add PublicResourceUrlProvider to get URLs for client-side use.

- Add ResourceUrlEncodingFilter and
  PublicResourceUrlProviderExposingInterceptor along with initial
  MVC Java config support.

Issue: SPR-10933