Asyncore logging exception on shutdown

logging module is being removed during interpreter shutdown but event loop is still trying to use it.

This error is being thrown from cqlsh during automaton test tests.tools.Copy_Test.TestCqlCopy.test_copy_with_null_entries_csv :
http://jenkins2.datastax.lan:8080/job/QA2_Cassandra_Tools/2581/AUTHENTICATION=dseauth_internal_dserc_file,PLATFORM=xenial,label_exp=qa_runner_dyna/testReport/junit/tests.tools.Copy_Test/TestCqlCopy/test_copy_with_null_entries_csv/

This will only be a problem for python <= 3.3:
https://stackoverflow.com/a/25649713/37205