bump development status

Author: nschloe

setup.cfg

@@ -14,7 +14,7 @@ long_description_content_type = text/markdown
 license = MIT
 license_file = LICENSE
 classifiers =
-    Development Status :: 4 - Beta
+    Development Status :: 5 - Production/Stable
     Framework :: Matplotlib
     License :: OSI Approved :: MIT License
     Operating System :: OS Independent