fix a few minor CLI bugs

see: https://github.com/ansible/awx/issues/4608

awx/main/migrations/0087_v360_update_credential_injector_help_text.py

@@ -0,0 +1,29 @@
+# Generated by Django 2.2.4 on 2019-08-27 21:50
+
+import awx.main.fields
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0086_v360_workflow_approval'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='credential',
+            name='inputs',
+            field=awx.main.fields.CredentialInputField(blank=True, default=dict, help_text='Enter inputs using either JSON or YAML syntax. Refer to the Ansible Tower documentation for example syntax.'),
+        ),
+        migrations.AlterField(
+            model_name='credentialtype',
+            name='injectors',
+            field=awx.main.fields.CredentialTypeInjectorField(blank=True, default=dict, help_text='Enter injectors using either JSON or YAML syntax. Refer to the Ansible Tower documentation for example syntax.'),
+        ),
+        migrations.AlterField(
+            model_name='credentialtype',
+            name='inputs',
+            field=awx.main.fields.CredentialTypeInputField(blank=True, default=dict, help_text='Enter inputs using either JSON or YAML syntax. Refer to the Ansible Tower documentation for example syntax.'),
+        ),
+    ]