* CI: replace travis with GitHub action matrix
The GitHub action runs the same tests as travis however using a more
complex matrix:
Python versions: 3.5, 3.6, 3.7, 3.8
Python 3.4 is dropped by redis-py, therefore not required in the tests.
Redis versions: 3, 4, 5, 6
The different Redis versions offer different features and this allows
checks for compatibility.
redis-py versions: 3.5.0, 3.5.3
3.5.0 is the oldest supported version, 3.5.3 is the latest upstream
verison
Signed-off-by: Paul Spooren <mail@aparcar.org>
* CI: Add flake8 lint action
This actions runs `flake8` and shows style problems of the code. It uses
th GitHub default options which handle most problems as warnings. These
rules could become slowly more strict.
Signed-off-by: Paul Spooren <mail@aparcar.org>