Indent messages correctly in DocumentationFormatter.

When using `example.reporter.message`, it would be nice if the messages were indented correctly, so that it's clear it relates to the current spec being executed.

Author: ioquatix

lib/rspec/core/formatters/documentation_formatter.rb

@@ -38,6 +38,10 @@ def example_failed(failure)
           output.puts failure_output(failure.example)
         end
 
+        def message(notification)
+          output.puts "#{current_indentation}#{notification.message}"
+        end
+
       private
 
         def passed_output(example)