Do generates the report of the Results received.
This function uses the log package in gremlins to write to the
chosen io.Writer, so it is necessary to call log.Init before
the report generation.
Mutant logs a mutator.Mutator.
It reports the mutant.Status, the mutator.Type and its position.
This function uses the log package in gremlins to write to the
chosen io.Writer, so it is necessary to call log.Init before
the report generation.