Fix merge issues on stdout branch

The act of committing a PR that including part of these changes and then
reverting it meant that some of the changes from the original branch
didn't land in this new PR.   This commit adds the missing bits.

Lesson learned:  Create a new branch when submitting a PR on a
previously reverted PR

awx/api/views.py

@@ -25,6 +25,8 @@ from django.utils.safestring import mark_safe
 from django.utils.timezone import now
 from django.views.decorators.csrf import csrf_exempt
 from django.template.loader import render_to_string
+from django.core.servers.basehttp import FileWrapper
+from django.http import HttpResponse
 
 # Django REST Framework
 from rest_framework.exceptions import PermissionDenied, ParseError
@@ -2789,7 +2791,7 @@ class UnifiedJobStdout(RetrieveAPIView):
     serializer_class = UnifiedJobStdoutSerializer
     renderer_classes = [BrowsableAPIRenderer, renderers.StaticHTMLRenderer,
                         PlainTextRenderer, AnsiTextRenderer,
-                        renderers.JSONRenderer]
+                        renderers.JSONRenderer, DownloadTextRenderer]
     filter_backends = ()
     new_in_148 = True