Fix ModelViewSet Nested bug (#65)

* Add todo repro app
* Add explicit test against model named "Nested"
* Force serializers named NestedSerializer to be output as inline models
* Allow ref_name to rescue a NestedSerializer
* Add tests and documentation

testproj/testproj/settings/base.py

@@ -26,6 +26,7 @@ INSTALLED_APPS = [
     'snippets',
     'users',
     'articles',
+    'todo',
 ]
 
 MIDDLEWARE = [

testproj/testproj/urls.py

@@ -62,5 +62,6 @@ urlpatterns = [
     url(r'^snippets/', include('snippets.urls')),
     url(r'^articles/', include('articles.urls')),
     url(r'^users/', include('users.urls')),
+    url(r'^todo/', include('todo.urls')),
     url(r'^plain/', plain_view),
 ]