Make MediaType serializable

Issue: SPR-8738
Allow custom expand algorithm in UriComponents

Issue: SPR-10647
Add Jackson serialization inclusion to FactoryBean

Issue: SPR-10810
Support placeholder values in Spring MVC Test

Issue: SPR-10825
Modify how SpringConfigurator finds Endpoint singleton

First try the endpoint type name converted to property
Then try @Component value

Issue: SPR-10605
Fix NPE in ResourceHttpMessageConverter

ResourceHttpMessageConverter tries to use the filename to determine the
media type, but for Resource implementations such as ByteArrayResource
it is null, which causes NullPointerException. The fix checks whether
getFilename returns null before attempting to determine the media type
by it.

Issue: SPR-10848