tests: replace pycodestyle with black

Drop pycodestyle for code style checking in favor of black. Black is
much faster, stable PEP8 compliant code style checker offering also
automatic formatting. It aims to be very stable and produce smallest
diffs. It's used by many small and big projects.

Running checkstyle with black takes a few seconds with a terse output.
Thus, test-checkstyle-diff is no longer necessary.

Expand scope of checkstyle to all python files in the repo, replacing
test-checkstyle with checkstyle-python.

Also, fixstyle-python is now available for automatic style formatting.

Note: python virtualenv has been consolidated in test/Makefile,
test/requirements*.txt which will eventually be moved to a central
location.  This is required to simply the automated generation of
docker executor images in the CI.

Type: improvement
Change-Id: I022a326603485f58585e879ac0f697fceefbc9c8
Signed-off-by: Klement Sekera <klement.sekera@gmail.com>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/extras/vpp_config/setup.py b/extras/vpp_config/setup.py
index 64f75d7..010920b 100644
--- a/extras/vpp_config/setup.py
+++ b/extras/vpp_config/setup.py
@@ -1,33 +1,31 @@
 from setuptools import setup
 
-setup(name="vpp_config",
-      version="20.05.1",
-      author="John DeNisco",
-      author_email="jdenisco@cisco.com",
-      description="VPP Configuration Utility",
-      license='Apache-2.0',
-      keywords="vppconfig",
-      url='https://wiki.fd.io/view/VPP',
-      py_modules=['vpp_config'],
-      install_requires=['distro', 'pyyaml', 'requests'],
-      extra_requires=["ipaddress; python_version < '3.3'"],
-      packages=['vpplib'],
-      entry_points={
-          'console_scripts': ['vpp-config=vpp_config:config_main'],
-      },
-      data_files=[('vpp/vpp-config/scripts', ['scripts/dpdk-devbind.py']),
-                  ('vpp/vpp-config/configs', ['data/auto-config.yaml']),
-                  ('vpp/vpp-config/configs', ['data/cloud-config.iso']),
-                  ('vpp/vpp-config/configs',
-                   ['data/iperf-centos.xml.template']),
-                  ('vpp/vpp-config/configs',
-                   ['data/iperf-ubuntu.xml.template']),
-                  ('vpp/vpp-config/dryrun/sysctl.d',
-                   ['data/80-vpp.conf.template']),
-                  ('vpp/vpp-config/dryrun/default', ['data/grub.template']),
-                  ('vpp/vpp-config/dryrun/vpp',
-                   ['data/startup.conf.template']),
-                  ],
-      long_description="The VPP configuration utility can be used to "
-                       "easily configure VPP.",
-      )
+setup(
+    name="vpp_config",
+    version="20.05.1",
+    author="John DeNisco",
+    author_email="jdenisco@cisco.com",
+    description="VPP Configuration Utility",
+    license="Apache-2.0",
+    keywords="vppconfig",
+    url="https://wiki.fd.io/view/VPP",
+    py_modules=["vpp_config"],
+    install_requires=["distro", "pyyaml", "requests"],
+    extra_requires=["ipaddress; python_version < '3.3'"],
+    packages=["vpplib"],
+    entry_points={
+        "console_scripts": ["vpp-config=vpp_config:config_main"],
+    },
+    data_files=[
+        ("vpp/vpp-config/scripts", ["scripts/dpdk-devbind.py"]),
+        ("vpp/vpp-config/configs", ["data/auto-config.yaml"]),
+        ("vpp/vpp-config/configs", ["data/cloud-config.iso"]),
+        ("vpp/vpp-config/configs", ["data/iperf-centos.xml.template"]),
+        ("vpp/vpp-config/configs", ["data/iperf-ubuntu.xml.template"]),
+        ("vpp/vpp-config/dryrun/sysctl.d", ["data/80-vpp.conf.template"]),
+        ("vpp/vpp-config/dryrun/default", ["data/grub.template"]),
+        ("vpp/vpp-config/dryrun/vpp", ["data/startup.conf.template"]),
+    ],
+    long_description="The VPP configuration utility can be used to "
+    "easily configure VPP.",
+)