message: use requirements file for appveyor
diff: @@ -48,8 +48,8 @@ install:
  - python --version
  - pip --version
  - python -m pip install --upgrade pip
  - - pip install -U setuptools numpy matplotlib scipy Cython pytest
  - - pip install -U POT pybind11
  + - python -m pip install --user -r .github/build-requirements.txt
  + - python -m pip install --user -r .github/test-requirements.txt
  build_script:
  - mkdir build
  