Final improvements before uploading v5.0 to PyPi

Add proper Python classifiers. Test with Python 3.9 in CI.

Author: kblomqvist

.travis.yml

@@ -3,6 +3,7 @@ python:
   - 3.6
   - 3.7 # Debian Buster
   - 3.8
+  - 3.9
   - nightly
 
 install:

setup.cfg

@@ -1,3 +1,3 @@
 [metadata]
-long_description=file: README.md
-long_description_content_type=text/markdown
+long_description = file:README.md
+long_description_content_type = text/markdown

setup.py

@@ -34,6 +34,13 @@
         "Topic :: Software Development :: Code Generators",
         "Development Status :: 5 - Production/Stable",
         "License :: OSI Approved :: MIT License",
+        "Programming Language :: Python",
+        "Programming Language :: Python :: 3",
+        "Programming Language :: Python :: 3 :: Only",
+        "Programming Language :: Python :: 3.6",
+        "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
     ],
     url="https://github.com/kblomqvist/yasha",
     download_url="https://github.com/kblomqvist/yasha/tarball/" + __version__,