Fix package description

setup.cfg

@@ -4,6 +4,7 @@ author = Johannes Hoppe
 author_email = info@johanneshoppe.com
 description = A lightweight file uploader input for Django and Amazon S3
 long_description = file: README.rst
+long_description_content_type = text/x-rst
 url = https://github.com/codingjoe/django-s3file
 license = MIT
 license_file = LICENSE
@@ -15,14 +16,16 @@ classifier =
     License :: OSI Approved :: MIT License
     Operating System :: OS Independent
     Programming Language :: Python
+    Programming Language :: JavaScript
     Topic :: Software Development
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3 :: Only
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
     Framework :: Django
-    Framework :: Django :: 1.11
     Framework :: Django :: 2.2
+    Framework :: Django :: 3.1
 
 [options]
 include_package_data = True