chore: remove old Django version conditionals

Author: jerivas

mezzanine/boot/__init__.py

@@ -10,12 +10,10 @@
 """
 from collections import defaultdict
 
-from django import VERSION as DJANGO_VERSION
 from django.apps import apps
 from django.conf import settings
 from django.contrib import admin
 from django.core.exceptions import ImproperlyConfigured
-from django.db.models.signals import class_prepared
 
 from mezzanine.boot.lazy_admin import LazyAdminSite
 from mezzanine.utils.importing import import_dotted_path
@@ -89,12 +87,8 @@ def add_extra_model_fields(sender, **kwargs):
         field.contribute_to_class(sender, field_name)
 
 
-if DJANGO_VERSION < (1, 9):
-    if fields:
-        class_prepared.connect(add_extra_model_fields, dispatch_uid="FQFEQ#rfq3r")
-else:
-    for model_key in fields:
-        apps.lazy_model_operation(add_extra_model_fields, model_key)
+for model_key in fields:
+    apps.lazy_model_operation(add_extra_model_fields, model_key)
 
 
 # Override django.contrib.admin.site with LazyAdminSite. It must

mezzanine/core/apps.py

@@ -1,4 +1,3 @@
-from django import VERSION as DJANGO_VERSION
 from django.apps import AppConfig
 
 
@@ -8,10 +7,3 @@ class CoreConfig(AppConfig):
 
     def ready(self):
         from . import checks  # noqa
-
-        if DJANGO_VERSION < (1, 9):
-            # add_to_builtins was removed in 1.9 and replaced with a
-            # documented public API configured by the TEMPLATES setting.
-            from django.template.base import add_to_builtins
-
-            add_to_builtins("mezzanine.template.loader_tags")

mezzanine/template/__init__.py

@@ -1,7 +1,6 @@
 import warnings
 from functools import wraps
 
-from django import VERSION as DJANGO_VERSION
 from django import template
 
 
@@ -20,7 +19,7 @@ def as_tag(self, tag_func):
         ``var_name`` in the template.
         """
         package = tag_func.__module__.split(".")[0]
-        if DJANGO_VERSION >= (1, 9) and package != "mezzanine":
+        if package != "mezzanine":
             warnings.warn(
                 "The `as_tag` template tag builder is deprecated in favour of "
                 "Django's built-in `simple_tag`, which supports variable "