Don't pin dependencies in setup.py

As explained in
https://packaging.python.org/discussions/install-requires-vs-requirements/#install-requires.
It is not recommended (can confirm) to pin dependencies to a specific
version in install_requires.

setup.py

@@ -9,7 +9,7 @@ from setuptools.command.test import test as TestCommand
 
 
 class PyTestCommand(TestCommand):
-    user_options = [('pytest-args=', 'a', 'Arguments to pass to py.test')]
+    user_options = [("pytest-args=", "a", "Arguments to pass to py.test")]
 
     def initialize_options(self):
         TestCommand.initialize_options(self)
@@ -22,71 +22,121 @@ class PyTestCommand(TestCommand):
 
     def run_tests(self):
         import pytest  # noqa
+
         errno = pytest.main(self.pytest_args)
         sys.exit(errno)
 
 
 def read(*parts):
     here = os.path.abspath(os.path.dirname(__file__))
-    with open(os.path.join(here, *parts), 'r') as fp:
+    with open(os.path.join(here, *parts), "r") as fp:
         return fp.read()
 
 
-def get_requirements(e=None):
-    rf = "requirements.txt" if e is None else 'requirements-{}.txt'.format(e)
-    r = read(rf)
-    return [x.strip() for x in r.split('\n')
-            if not x.startswith('#') and not x.startswith("-e")]
-
-
 long_description = read("README.md")
-install_requires = get_requirements()
+install_requires = [
+    "alembic",
+    "amqp",
+    "attrs",
+    "Babel",
+    "billiard",
+    "blinker",
+    "celery",
+    "certifi",
+    "chardet",
+    "click",
+    "click-log",
+    "enum34",
+    "Flask",
+    "Flask-Alembic",
+    "flask-allows",
+    "Flask-BabelPlus",
+    "Flask-Caching",
+    "Flask-DebugToolbar",
+    "flask-debugtoolbar-warnings",
+    "Flask-Limiter",
+    "Flask-Login",
+    "Flask-Mail",
+    "Flask-Redis",
+    "Flask-SQLAlchemy",
+    "Flask-Themes2",
+    "flask-whooshee",
+    "Flask-WTF",
+    "flaskbb-plugin-conversations",
+    "flaskbb-plugin-portal",
+    "idna",
+    "itsdangerous",
+    "Jinja2",
+    "kombu",
+    "limits",
+    "Mako",
+    "MarkupSafe",
+    "mistune",
+    "olefile",
+    "Pillow",
+    "pluggy",
+    "Pygments",
+    "python-dateutil",
+    "python-editor",
+    "pytz",
+    "redis",
+    "requests",
+    "simplejson",
+    "six",
+    "speaklater",
+    "SQLAlchemy",
+    "SQLAlchemy-Utils",
+    "Unidecode",
+    "urllib3",
+    "vine",
+    "Werkzeug",
+    "Whoosh",
+    "WTForms",
+]
 
+extras_require = {"postgres": ["psycopg2-binary"]}
+
+tests_require = ["py", "pytest", "pytest-cov", "cov-core", "coverage"]
 
 setup(
-    name='FlaskBB',
+    name="FlaskBB",
     version="2.0.1",
-    url='https://flaskbb.org',
+    url="https://flaskbb.org",
     project_urls={
-        'Documentation': 'https://flaskbb.readthedocs.io/en/latest/',
-        'Code': 'https://github.com/flaskbb/flaskbb',
-        'Issue Tracker': 'https://github.com/flaskbb/flaskbb',
+        "Documentation": "https://flaskbb.readthedocs.io/en/latest/",
+        "Code": "https://github.com/flaskbb/flaskbb",
+        "Issue Tracker": "https://github.com/flaskbb/flaskbb",
     },
-    license='BSD',
-    author='Peter Justin',
-    author_email='peter.justin@outlook.com',
-    description='A classic Forum Software in Python using Flask.',
+    license="BSD",
+    author="Peter Justin",
+    author_email="peter.justin@outlook.com",
+    description="A classic Forum Software in Python using Flask.",
     long_description=long_description,
-    long_description_content_type='text/markdown',
+    long_description_content_type="text/markdown",
     packages=find_packages(),
     include_package_data=True,
     zip_safe=False,
-    platforms='any',
-    entry_points='''
+    platforms="any",
+    entry_points="""
         [console_scripts]
         flaskbb=flaskbb.cli:flaskbb
-    ''',
-    python_requires='>=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*',
+    """,
+    python_requires=">=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*",
     install_requires=install_requires,
-    tests_require=[
-        'py',
-        'pytest',
-        'pytest-cov',
-        'cov-core',
-        'coverage'
-    ],
-    test_suite='tests',
+    extras_require=extras_require,
+    tests_require=tests_require,
+    test_suite="tests",
     classifiers=[
-        'Development Status :: 4 - Beta',
-        'Environment :: Web Environment',
-        'Intended Audience :: Developers',
-        'Intended Audience :: End Users/Desktop',
-        'License :: OSI Approved :: BSD License',
-        'Operating System :: OS Independent',
-        'Programming Language :: Python',
-        'Programming Language :: Python :: 3',
-        'Topic :: Internet :: WWW/HTTP :: Dynamic Content',
-        'Topic :: Software Development :: Libraries :: Python Modules'
+        "Development Status :: 4 - Beta",
+        "Environment :: Web Environment",
+        "Intended Audience :: Developers",
+        "Intended Audience :: End Users/Desktop",
+        "License :: OSI Approved :: BSD License",
+        "Operating System :: OS Independent",
+        "Programming Language :: Python",
+        "Programming Language :: Python :: 3",
+        "Topic :: Internet :: WWW/HTTP :: Dynamic Content",
+        "Topic :: Software Development :: Libraries :: Python Modules",
     ],
-    cmdclass={'test': PyTestCommand}
+    cmdclass={"test": PyTestCommand},
 )