installation from pypi source package failing due to missing requirements.txt

[flotsan]

Installation using the source package downloaded from pypi (https://pypi.org/project/Flask-COMBO-JSONAPI/#files) would fail because "requirements.txt" used by setup.py wasn't included in the archive.

Steps to reproduce:

$ pip install Flask-COMBO-JSONAPI-1.1.0.tar.gz
Processing /tmp/Flask-COMBO-JSONAPI-1.1.0.tar.gz
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/var/folders/t7/t04m89ss3cj2x1bqv4gmqj5r000t9r/T/pip-req-build-6neyzad5/setup.py", line 8, in <module>
        with open(requirements_filepath) as fp:
    FileNotFoundError: [Errno 2] No such file or directory: 'requirements.txt'

    ----------------------------------------

It can be resolved if it is declared to be included in MANIFEST.in