Improve packaging by using PBR

PBR (Python Build Reasonableness)[1].

Overview:
- remove python code
- introduce meta project configuration
- allow pypi to display readme at markdown format
- automatize semver management based on git tag name (example 1.0.0)
- automatize changelog generate
- automatize authors file generate

PBR allow to automatically manage your version bumping,
your changelog, your authors file and a lot of useful
features like this.

You just have to publish a git tag and pbr generate
a version number based on the git tag name (example: 1.0.0).

It also a good practice to use setup.cfg to centralize
project configuration:
- project meta
- wheel
- etc...

This commit remove python code to maintain by transform it
into configuration.

If you choose to distribute this project with pypi these
changes introduce readme displayed at markdown format compatible
with pypi.

[1] https://docs.openstack.org/pbr/latest/

Signed-off-by: Hervé Beraud <hberaud@redhat.com>

setup.cfg

@@ -0,0 +1,46 @@
+[metadata]
+name = pypodman
+home-page = https://github.com/containers/python-pypodman
+project_urls =
+    Bug Tracker = https://github.com/containers/python-pypodman/issues
+    Source Code = https://github.com/containers/python-pypodman
+summary = A client for communicating with a Podman server
+description-file = 
+    README.md
+author = Jhon Honce
+author-email = jhonce@redhat.com
+license = Apache Software License
+classifier =
+    Development Status :: 3 - Alpha
+    Intended Audience :: Developers
+    Intended Audience :: System Administrators
+    License :: OSI Approved :: Apache Software License
+    Operating System :: MacOS :: MacOS X
+    Operating System :: Microsoft :: Windows
+    Operating System :: POSIX
+    Programming Language :: Python :: 3.4
+    Topic :: System :: Systems Administration
+    Topic :: Utilities
+keywords =
+    varlink
+    libpod
+    podman
+    pypodman
+
+[files]
+packages =
+    pypodman
+
+[extras]
+devel=
+    fixtures
+    pbr
+    tox
+    bandit
+
+[entry_points]
+console_scripts =
+    pypodman = pypodman.main:main
+
+[wheel]
+universal = 1

setup.py

@@ -1,45 +1,9 @@
 #!/usr/bin/env python
 
-import os
-
-from setuptools import find_packages, setup
-
-root = os.path.abspath(os.path.dirname(__file__))
-
-with open(os.path.join(root, 'README.md')) as me:
-    readme = me.read()
-
-with open(os.path.join(root, 'requirements.txt')) as r:
-    requirements = r.read().splitlines()
-
+from setuptools import setup
 
 setup(
-    name='pypodman',
-    version=os.environ.get('PODMAN_VERSION', '0.0.0'),
-    description='A client for communicating with a Podman server',
-    author_email='jhonce@redhat.com',
-    author='Jhon Honce',
-    license='Apache Software License',
-    long_description=readme,
-    entry_points={'console_scripts': [
-        'pypodman = pypodman.main:main',
-    ]},
-    include_package_data=True,
-    install_requires=requirements,
-    packages=find_packages(exclude=['test']),
-    python_requires='>=3',
-    zip_safe=True,
-    url='http://github.com/containers/libpod',
-    keywords='varlink libpod podman pypodman',
-    classifiers=[
-        'Development Status :: 3 - Alpha',
-        'Intended Audience :: Developers',
-        'Intended Audience :: System Administrators',
-        'License :: OSI Approved :: Apache Software License',
-        'Operating System :: MacOS :: MacOS X',
-        'Operating System :: Microsoft :: Windows',
-        'Operating System :: POSIX',
-        'Programming Language :: Python :: 3.4',
-        'Topic :: System :: Systems Administration',
-        'Topic :: Utilities',
-    ])
+    setup_requires=['pbr'],
+    pbr=True,
+    long_description_content_type="text/markdown",
+)