Removed module-level functions for the app cache.

Since the original ones in django.db.models.loading were kept only for
backwards compatibility, there's no need to recreate them. However, many
internals of Django still relied on them.

They were also imported in django.db.models. They never appear in the
documentation, except a quick mention of get_models and get_app in the
1.2 release notes to document an edge case in GIS. I don't think that
makes them a public API.

This commit doesn't change the overall amount of global state but
clarifies that it's tied to the app_cache object instead of hiding it
behind half a dozen functions.

django/contrib/admindocs/views.py

@@ -4,6 +4,7 @@ import os
 import re
 
 from django import template
+from django.apps import app_cache
 from django.conf import settings
 from django.contrib import admin
 from django.contrib.admin.views.decorators import staff_member_required
@@ -182,7 +183,7 @@ class ModelIndexView(BaseAdminDocsView):
     template_name = 'admin_doc/model_index.html'
 
     def get_context_data(self, **kwargs):
-        m_list = [m._meta for m in models.get_models()]
+        m_list = [m._meta for m in app_cache.get_models()]
         kwargs.update({'models': m_list})
         return super(ModelIndexView, self).get_context_data(**kwargs)
 
@@ -193,11 +194,11 @@ class ModelDetailView(BaseAdminDocsView):
     def get_context_data(self, **kwargs):
         # Get the model class.
         try:
-            app_mod = models.get_app(self.kwargs['app_label'])
+            app_mod = app_cache.get_app(self.kwargs['app_label'])
         except ImproperlyConfigured:
             raise Http404(_("App %r not found") % self.kwargs['app_label'])
         model = None
-        for m in models.get_models(app_mod):
+        for m in app_cache.get_models(app_mod):
             if m._meta.model_name == self.kwargs['model_name']:
                 model = m
                 break