Py3 support

[user2589]

a small step for humanity, but a huge leap for WoC Python users:

• Python 3 support. It means finally we don't have to look for a set of Py2-compatible libraries to work with
• Major performance improvements after migrating to Cython
• Compatibility - oscar now includes libtokyocabinet compiled to be compatible with WoC (default ubuntu version is not)
• Testability - sources now include small fixtures that allow to run most unit tests locally; this is already integrated in github workflow
• Simplified development - since tests aren't tied to UTK servers anymore, we can stick with master+feature branches model

[audrism]

Happy New Year Marat!

[audrism]

@user2589 the setup.py wants to have oscar.py file: which is no longer there, hence build fails

Specifically: in the step: Run relekang/python-semantic-release@v7.9.0 the build runs:

/usr/bin/docker run --name cc4956ce442f90fa224fca84c46e3630627776_5238c3 --label cc4956 --workdir /github/workspace --rm -e pythonLocation -e LD_LIBRARY_PATH -e INPUT_GITHUB_TOKEN -e INPUT_PYPI_TOKEN -e INPUT_DIRECTORY -e INPUT_PYPI_USERNAME -e INPUT_PYPI_PASSWORD -e HOME -e GITHUB_JOB -e GITHUB_REF -e GITHUB_SHA -e GITHUB_REPOSITORY -e GITHUB_REPOSITORY_OWNER -e GITHUB_RUN_ID -e GITHUB_RUN_NUMBER -e GITHUB_RETENTION_DAYS -e GITHUB_ACTOR -e GITHUB_WORKFLOW -e GITHUB_HEAD_REF -e GITHUB_BASE_REF -e GITHUB_EVENT_NAME -e GITHUB_SERVER_URL -e GITHUB_API_URL -e GITHUB_GRAPHQL_URL -e GITHUB_WORKSPACE -e GITHUB_ACTION -e GITHUB_EVENT_PATH -e GITHUB_ACTION_REPOSITORY -e GITHUB_ACTION_REF -e GITHUB_PATH -e GITHUB_ENV -e RUNNER_OS -e RUNNER_TOOL_CACHE -e RUNNER_TEMP -e RUNNER_WORKSPACE -e ACTIONS_RUNTIME_URL -e ACTIONS_RUNTIME_TOKEN -e ACTIONS_CACHE_URL -e GITHUB_ACTIONS=true -e CI=true -v "/var/run/docker.sock":"/var/run/docker.sock" -v "/home/runner/work/_temp/_github_home":"/github/home" -v "/home/runner/work/_temp/_github_workflow":"/github/workflow" -v "/home/runner/work/_temp/_runner_file_commands":"/github/file_commands" -v "/home/runner/work/oscar.py/oscar.py":"/github/workspace" cc4956:ce442f90fa224fca84c46e3630627776