DATAMONGO-973 - Add support for deriving full-text queries.

Added support to execute full-text queries on repositories. Query methods now can have a parameter of type TextCriteria which will be triggering a text search clause for the property annotated with @TestScore.

Retrieving document score and sorting by score is only possible if the entity holds a property annotated with @TextScore. If present, any find execution will be enriched so that it asserts loading of the according { $meta : textScore } field. The sort object will only be mapped in case the existing sort property already exists - in that case we replace the existing expression for the property with its $meta representation.

This allows for example the following:

TextCriteria criteria = TextCriteria.forDefaultLanguage().matching("term");

repository.findAllBy(criteria, new Sort("score"));
repository.findAllBy(criteria, new PageRequest(0, 10, Direction.DESC, "score"));
repository.findByFooOrderByScoreDesc("foo", criteria);

For more details and examples see the "Full text search queries" section in the reference manual.