create new bulk host create endpoint

allow system admins, org admins, and inventory admins to bulk create
hosts.

Testing on an "open" licensed awx as system admin, I created 1000 hosts with 6 queries in ~ 0.15 seconds
Testing on an "open" licensed awx as organization admin, I created 1000 hosts with 11 queries in ~ 0.15 seconds

fix org max host check

also only do permission denied if license is a trial

add /api/v2/bulk to list bulk apis available

add api description templates

One motiviation to not take a list of hosts with mixed inventories is to
keep things simple re: RBAC and keeping a constant number of queries.

If there is great clamor for accepting list of hosts to insert into
arbitrary different inventories, we could probably make it happen - we'd
need to pop the inventory off of each of the hosts, run the
HostSerializer validate, then in top level BulkHostCreateSerializer
fetch all the inventories/check permissions/org host limits for those
inventories/etc. But that makes this that much more complicated.

add test for rbac access

test also helped me find a bug in a query, fixed that

add test to assert num queries scales as expected

also move other test to dedicated file

also test with super user like I meant to

record activity stream for the inventory

this records that a certain number of hosts were added by a certain user
we could consider if there is any other additional information we want
to include

awx/main/tests/functional/test_bulk.py

@@ -0,0 +1,86 @@
+import pytest
+
+from uuid import uuid4
+
+from awx.api.versioning import reverse
+
+import json
+from contextlib import contextmanager
+from django.test.utils import CaptureQueriesContext
+from django.db import connections
+
+
+@contextmanager
+def withAssertNumQueriesLessThan(num_queries):
+    with CaptureQueriesContext(connections['default']) as context:
+        yield
+        fail_msg = f"\r\n{json.dumps(context.captured_queries, indent=4)}"
+    assert len(context.captured_queries) < num_queries, fail_msg
+
+
+@pytest.mark.django_db
+@pytest.mark.parametrize('num_hosts, num_queries', [(9, 15), (99, 20), (999, 25)])
+def test_bulk_host_create_num_queries(organization, inventory, post, get, user, num_hosts, num_queries):
+    '''
+    If I am a...
+      org admin
+      inventory admin at org level
+      admin of a particular inventory
+      superuser
+
+    Bulk Host create should take under a certain number of queries
+    '''
+    inventory.organization = organization
+    inventory_admin = user('inventory_admin', False)
+    org_admin = user('org_admin', False)
+    org_inv_admin = user('org_admin', False)
+    superuser = user('admin', True)
+    for u in [org_admin, org_inv_admin, inventory_admin]:
+        organization.member_role.members.add(u)
+    organization.admin_role.members.add(org_admin)
+    organization.inventory_admin_role.members.add(org_inv_admin)
+    inventory.admin_role.members.add(inventory_admin)
+
+    for u in [org_admin, inventory_admin, org_inv_admin, superuser]:
+        hosts = [{'name': uuid4()} for i in range(num_hosts)]
+        with withAssertNumQueriesLessThan(num_queries):
+            bulk_host_create_response = post(reverse('api:bulk_host_create'), {'inventory': inventory.id, 'hosts': hosts}, u, expect=201).data
+            assert bulk_host_create_response['created'] == len(hosts), f"unexpected number of hosts created for user {u}"
+
+
+@pytest.mark.django_db
+def test_bulk_host_create_rbac(organization, inventory, post, get, user):
+    '''
+    If I am a...
+      org admin
+      inventory admin at org level
+      admin of a particular invenotry
+          ... I can bulk add hosts
+
+    Everyone else cannot
+    '''
+    inventory.organization = organization
+    inventory_admin = user('inventory_admin', False)
+    org_admin = user('org_admin', False)
+    org_inv_admin = user('org_admin', False)
+    auditor = user('auditor', False)
+    member = user('member', False)
+    use_inv_member = user('member', False)
+    for u in [org_admin, org_inv_admin, auditor, member, inventory_admin, use_inv_member]:
+        organization.member_role.members.add(u)
+    organization.admin_role.members.add(org_admin)
+    organization.inventory_admin_role.members.add(org_inv_admin)
+    inventory.admin_role.members.add(inventory_admin)
+    inventory.use_role.members.add(use_inv_member)
+    organization.auditor_role.members.add(auditor)
+
+    for indx, u in enumerate([org_admin, inventory_admin, org_inv_admin]):
+        bulk_host_create_response = post(
+            reverse('api:bulk_host_create'), {'inventory': inventory.id, 'hosts': [{'name': f'foobar-{indx}'}]}, u, expect=201
+        ).data
+        assert bulk_host_create_response['created'] == 1, f"unexpected number of hosts created for user {u}"
+
+    for indx, u in enumerate([member, auditor, use_inv_member]):
+        bulk_host_create_response = post(
+            reverse('api:bulk_host_create'), {'inventory': inventory.id, 'hosts': [{'name': f'foobar2-{indx}'}]}, u, expect=400
+        ).data