DATAMONGO-901 - Fixed regression of not registering type predicting post processor.

The changes for DATAMONGO-843 introduced a regression by skipping the registration of the RepositoryInterfaceAwareBeanPostProcessor. This can cause the wiring of repository bean definitions to fail depending on in which order the bean definitions get instantiated.

This change reintroduces the registration and adds an explicit test case for it.
DATAMONGO-888 - Mapping should be applied to Sort.

Prepare issue branch.
DATAMONGO-888 - Mapping should be applied to Sort.

EntityBackedSortConverter, as an instance of SortConverter, takes care of mapping properties to the according names to be used with mongodb.

Conversion will inspect properties within the backing entity to resolve ids and additional mapping information within the Field annotation and apply those to the resulting DBObject.

The converter will not touch any properties unknown to the backing entity.

getSortObject() has been deprecated and will be removed in a subsequent version.