This member is added by an implicit conversion from ReplaceRootField to
any2stringadd[ReplaceRootField] performed by method any2stringadd in scala.Predef.
This member is added by an implicit conversion from ReplaceRootField to
StringFormat[ReplaceRootField] performed by method StringFormat in scala.Predef.
(Since version 0.12-RC5) Use reactivemongo.api.collections.GenericCollection.aggregateWith