Upgrade code to Python 3.6+, Django 2.2 and remove deprecations

Author: bashu

example/urls.py

@@ -1,6 +1,6 @@
-from django.conf.urls import url
+from django.urls import path
 from django.contrib import admin
 
 urlpatterns = [
-    url(r"^admin/", admin.site.urls),
+    path('admin/', admin.site.urls),
 ]

taggit_anywhere/admin.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 from django.apps import apps
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured

taggit_anywhere/apps.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 from django.apps import AppConfig as DefaultAppConfig
 from django.apps import apps