CXX-934 Remove the unwanted and unimplemented database::stats helper declaration

Author: acmorrow

src/mongocxx/database.hpp

@@ -158,15 +158,6 @@ class MONGOCXX_API database {
  ///
  stdx::string_view name() const;
 
- ///
- /// Get server-side statistics for the database.
- ///
- /// @return document containing statistics for this database.
- ///
- /// @see http://docs.mongodb.org/manual/reference/command/dbStats/
- ///
- bsoncxx::document::value stats();
-
  ///
  /// Sets the read_concern for this database.
  ///