This PR clarifies how to test memtier_benchmark locally and uses the exact same script for CI testing.

Details on how to to test memtier:

The project includes a basic set of integration tests.

Integration tests

Integration tests are based on RLTest, and specific setup parameters can be provided
to configure tests and topologies (OSS standalone and OSS cluster). By default the tests will be ran for all common commands, and with OSS standalone setup.

To run all integration tests in a Python virtualenv, follow these steps:

$ mkdir -p .env
$ virtualenv .env
$ source .env/bin/activate
$ pip install -r tests/test_requirements.txt
$ ./tests/run_tests.sh

To understand what test options are available simply run:

$ ./tests/run_tests.sh --help