Split templates and tests in scenario tests

- Added subdirectory "templates" for storing all templates used in
  scenario tests.
- Added parameter sub_dir for method _load_template.
- Inline template was moved in templates directory from
  test_neutron_autoscaling.

Change-Id: I1acaf1ccc1466cf7ffc2e004eff486f49f4b5928
diff --git a/scenario/test_server_cfn_init.py b/scenario/test_server_cfn_init.py
index 64b2a35..630e2e9 100644
--- a/scenario/test_server_cfn_init.py
+++ b/scenario/test_server_cfn_init.py
@@ -27,6 +27,7 @@
             raise self.skipException("No image configured to test")
         self.client = self.orchestration_client
         self.template_name = 'test_server_cfn_init.yaml'
+        self.sub_dir = 'templates'
 
     def assign_keypair(self):
         self.stack_name = self._stack_rand_name()
@@ -48,7 +49,8 @@
         }
 
         # create the stack
-        self.template = self._load_template(__file__, self.template_name)
+        self.template = self._load_template(__file__, self.template_name,
+                                            self.sub_dir)
         self.client.stacks.create(
             stack_name=self.stack_name,
             template=self.template,