Spring Boot integration: Add interceptor logic to store marked objects at end of method.

[rdebusscher]

In order to align the functionality of the integrations, add interceptor logic to store marked objects at end of method.

This is similar to the functionality added in #377

We can collect the changed objects (objects marked as dirty) using a fluent API and those are stored at the end of the method

public interface DirtyMarker {
T mark(T instance);
}
This integration allows to clearly indicate what is changed and stores the changes in an asynchronous way (synchronous is also possible through the annotation or configuration).

[rdebusscher]

Also adds interfaces EmbeddedStorageFoundationCustomizer and StorageManagerInitializer to customize the Spring beans.