Fix erronous singleton role created for users

Needed to be just a normal role, ie with `name` assigned instead of
`singleton_name`

 Addresses #1499

awx/main/signals.py

@@ -126,7 +126,7 @@ def create_user_role(instance, **kwargs):
         instance.admin_role
     except Role.DoesNotExist:
         role = Role.objects.create(
-            singleton_name = '%s-admin_role' % instance.username,
+            name = '%s-admin_role' % instance.username,
             content_object = instance,
         )
         role.members.add(instance)

awx/main/tests/functional/api/test_user.py

@@ -0,0 +1,68 @@
+import pytest
+
+from django.core.urlresolvers import reverse
+
+
+#
+# user creation
+#
+
+@pytest.mark.django_db
+def test_user_create(post, admin):
+    response = post(reverse('api:user_list'), {
+        "username": "affable",
+        "first_name": "a",
+        "last_name": "a",
+        "email": "a@a.com",
+        "is_superuser": False,
+        "password": "fo0m4nchU"
+    }, admin)
+    assert response.status_code == 201
+
+@pytest.mark.django_db
+def test_fail_double_create_user(post, admin):
+    response = post(reverse('api:user_list'), {
+        "username": "affable",
+        "first_name": "a",
+        "last_name": "a",
+        "email": "a@a.com",
+        "is_superuser": False,
+        "password": "fo0m4nchU"
+    }, admin)
+    assert response.status_code == 201
+
+    response = post(reverse('api:user_list'), {
+        "username": "affable",
+        "first_name": "a",
+        "last_name": "a",
+        "email": "a@a.com",
+        "is_superuser": False,
+        "password": "fo0m4nchU"
+    }, admin)
+    assert response.status_code == 400
+
+@pytest.mark.django_db
+def test_create_delete_create_user(post, delete, admin):
+    response = post(reverse('api:user_list'), {
+        "username": "affable",
+        "first_name": "a",
+        "last_name": "a",
+        "email": "a@a.com",
+        "is_superuser": False,
+        "password": "fo0m4nchU"
+    }, admin)
+    assert response.status_code == 201
+
+    response = delete(reverse('api:user_detail', args=(response.data['id'],)), admin)
+    assert response.status_code == 204
+
+    response = post(reverse('api:user_list'), {
+        "username": "affable",
+        "first_name": "a",
+        "last_name": "a",
+        "email": "a@a.com",
+        "is_superuser": False,
+        "password": "fo0m4nchU"
+    }, admin)
+    print(response.data)
+    assert response.status_code == 201