update trove classifiers with more modern python versions

fixes #7

Author: dhellmann

setup.cfg

@@ -9,15 +9,12 @@ classifier =
     Development Status :: 5 - Production/Stable
     License :: OSI Approved :: MIT License
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.6
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.3
-    Programming Language :: Python :: 3.4
-    Programming Language :: Python :: 3.5
-    Programming Language :: Python :: 3.6
-    Intended Audience :: Developers
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
+Intended Audience :: Developers
     Environment :: Console
 keywords =
     virtualenv