docs: update README and remove Django 3.1 classifier

Author: asfaltboy

README.rst

@@ -26,7 +26,7 @@ For release notes, see `Changelog <https://raw.githubusercontent.com/modlinltd/d
 Requirements
 ============
 
--  Django 2.2, >= 3.1 on Python 3.6+/PyPy3
+-  Django 2.2, >= 3.2 on Python 3.6+/PyPy3
 -  simplejson >= 3.6.5, < 4
 
 

setup.py

@@ -85,7 +85,6 @@ def get_full_description():
         'Programming Language :: Python :: 3 :: Only',
         'Framework :: Django',
         'Framework :: Django :: 2.2',
-        'Framework :: Django :: 3.1',
         'Framework :: Django :: 3.2',
         'Framework :: Django :: 4.0',
         'Topic :: Internet :: WWW/HTTP',