Make database spec work for both single and replica set topologies
Make database spec work for both single and replica set topologies

mongodb/mongo-ruby-driver,brandonblack/mongo-ruby-driver,kay-kim/mongo-ruby-driver,saghm/mongo-ruby-driver,saghm/mongo-ruby-driver,kay-kim/mongo-ruby-driver,wandenberg/mongo-ruby-driver,jonhyman/mongo-ruby-driver,jonhyman/mongo-ruby-driver,estolfo/mongo-ruby-driver,mongodb/mongo-ruby-driver,estolfo/mongo-ruby-driver,mongodb/mongo-ruby-driver