Removes requirements.txt and no longer auto-parses requirements in setup.py

This is because pip version >= 10 no longer supports use of "parse_requirements".
Instead you can use the packaging library.
Further info in this issue in the pip repo:
https://github.com/pypa/pip/issues/5248

requirements.txt

-Django>=1.11,<3.0
-python3-saml
-
-# binary dependencies:
-# sudo apt install libxml2-dev libxslt1-dev xmlsec1 libxmlsec1-dev pkg-config

setup.py

 import os
 from setuptools import setup, find_packages
-from pip.req.req_file import parse_requirements
-from pip.download import PipSession
 
 README = open(os.path.join(os.path.dirname(__file__), "README.md")).read()
 
@@ -9,13 +7,6 @@ README = open(os.path.join(os.path.dirname(__file__), "README.md")).read()
 os.chdir(os.path.normpath(os.path.join(os.path.abspath(__file__), os.pardir)))
 
 
-def get_requirements_list():
-    filename = os.path.join(os.path.dirname(__file__), "requirements.txt")
-    objects = list(parse_requirements(filename, session=PipSession()))
-    strings = [str(o.req) for o in objects]
-    return strings
-
-
 setup(
     name='django-ssoauth',
     version='1.0',
@@ -28,7 +19,10 @@ setup(
     author='Art Lukyanchyk',
     author_email='artiom.lukyanchyk@hs-hannover.de',
     zip_safe=False,
-    install_requires=get_requirements_list(),
+    install_requires=[
+        'python3-saml',
+        'Django>=1.11,<3.0'
+    ],
     classifiers=[
         'Environment :: Web Environment',
         'Framework :: Django',
@@ -42,4 +36,5 @@ setup(
     ],
 )
 
-
+# binary dependencies:
+# sudo apt install libxml2-dev libxslt1-dev xmlsec1 libxmlsec1-dev pkg-config