fuel/core — pull request #641 by ipalaus (2011-11-02 15:02:43+00:00)
Title: Added Mongo_Db::get_one() to obtain only one document.

I have added `Mongo_Db::get_one()` that uses `MongoCollection::findOne` just for performance reasons: findOne is faster than find with a limit of 1.

I have done tests of 10.000 executions and that is what I've:

> Excuted in 1.07814502716 seconds, with an average of 0.00107814502716 sec/each - findOne
> Excuted in 1.17198491096 seconds, with an average of 0.00117198491096 sec/each - find