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* fix default_value issue when using with dict and list (see 35)
* fix bug reported by Andrew Degtiariov : http://bit.ly/c1vcUv
* add clone and explain method to MongoDocumentCursor
* add distinct to cursor (thanks to Flaper87)
* fix index test
* fix : when a field is added to a saved document and not specified in the structure, the validation wasn't work properly
* use current database if DBRef has no database information. Please, see the doc
* support of pymongo 1.4