Tests for wait-for-it

• wait-for-it.py - pytests for wait-for-it.sh
• container-runners.py - Runs wait-for-it.py tests in multiple containers
• requirements.txt - pip requirements for container-runners.py

To run the basic tests:

python wait-for-it.py

Many of the issues encountered have been related to differences between operating system versions. The container-runners.py script provides an easy way to run the python wait-for-it.py tests against multiple system configurations:

pip install -r requirements.txt
python container-runners.py