packaging: add setup.cfg with description and classifiers

Signed-off-by: Florian Scherf <f.scherf@pengutronix.de>

setup.cfg

@@ -0,0 +1,26 @@
+[metadata]
+description = Flamingo is a python3-based, pelican-inspired static site generator
+long_description = file: README.rst
+license_file = LICENCE
+classifiers =
+    Development Status :: 4 - Beta
+    Environment :: Console
+    Environment :: Web Environment
+    Framework :: AsyncIO
+    Framework :: IPython
+    License :: OSI Approved :: Apache Software License
+    Natural Language :: English
+    Operating System :: Unix
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3 :: Only
+    Programming Language :: Python :: Implementation
+    Programming Language :: Python :: Implementation :: CPython
+    Topic :: Documentation
+    Topic :: Internet :: WWW/HTTP
+    Topic :: Software Development :: Documentation
+    Topic :: Text Processing
+    Topic :: Text Processing :: Markup :: HTML
+    Topic :: Text Processing :: Markup :: XML
+    Topic :: Utilities