Revert "QPID-5812: python high level API client receiver.fetch(timeout=N) blocks forever in select() if broker is stopped (kill -STOP)"

This reverts commit r1602221 As it breaks the C++ tests:
- python_tests
- federation_sys_tests
- legacystore_python_tests

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1602302 13f79535-47bb-0310-9956-ffa450edef68