MongoDBCollection maintenance

[jmmut]

Is this class (or MongoDBNativeQuery) worth in the way it is done?

I mean for example, here opencb/opencga#112, at creating indices, the MongoDBCollection API is outdated, because it lacks the method public void createIndex( final String name ). I feel that I don't understand the motivation of maintaining this layers via composition, if we are going to be forced to replicate any API changes in mongo.

The quick solution is adding this method, but maybe at medium-long-term other options are more productive.