Clean up key_options_spec
Clean up usage of doubles in document_spec

* instance_double for the Database
* Remove unnecessary doubles
Clean up usage of doubles in configuration_spec

* Use an instance double of the Ruby logger as the logger double
* Use an instance double from our Connection
* Use real values for the other values, except the adapter
    * The adapter is an implementation detail of a dependency
Clean up usage of doubles in connection_spec
Clean up usage of doubles in cursor_spec
Clean up usage of doubles in edge_spec
Clean up usage of doubles in index_spec

unique is a 'Boolean' double, because I don't want to test both cases
separately and there is no boolean type in Ruby :wink:
Clean up usage of doubles in figure_spec

Removing the figures JSON by the way.
Clean up usage of doubles in exception_spec
Clean up usage of doubles in transaction_spec
Clean up usage of doubles in query_spec
Clean up usage of doubles in database_spec
Clean up usage of doubles in collection_spec