Refactor test_endless_data_attack.py

Refactored 'test_endless_data_attack.py' to use the 'unittest' module (test
conditions in code, rather than verifying text output), use pre-generated
repository files, and discontinue use of the old repository tools. Minor
edits to the test cases.
Merge pull request #195 from vladimir-v-diaz/refactor_test_endless_data_attack

Refactor test_endless_data_attack.py