Update documentation to reflect deprecation of MongoFactoryBean [DATAMONGO-1270]

[spring-projects-issues]

Timo Kockert opened DATAMONGO-1270 and commented

The current documentation of Spring Data MongoDB suggests to create a MongoFactoryBean to make a Mongo instance available in the context. However, MongoFactoryBean is deprecated in favor of MongoClientFactoryBean

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Reference URL: http://docs.spring.io/spring-data/mongodb/docs/current/reference/html/#mongo.mongo-java-config

Referenced from: pull request #315, and commits 38b7a72, bd81e25, 419d0a4

Backported to: 1.8.4 (Gosling SR4), 1.7.3 (Fowler SR3)