Fix duplicate callback issue in v2

All v2+ callbacks can now optionally define a CALLBACK_TYPE, which
when set to 'stdout' will limit those callbacks which are used for
primary output to a single callback plugin (specified to the
TaskQueueManager object and configurable in ansible.cfg/environment)

v2/ansible/plugins/__init__.py

@@ -243,9 +243,12 @@ class PluginLoader:
                 if path not in self._module_cache:
                     self._module_cache[path] = imp.load_source('.'.join([self.package, name]), path)
                 if kwargs.get('class_only', False):
-                    yield getattr(self._module_cache[path], self.class_name)
+                    obj = getattr(self._module_cache[path], self.class_name)
                 else:
-                    yield getattr(self._module_cache[path], self.class_name)(*args, **kwargs)
+                    obj = getattr(self._module_cache[path], self.class_name)(*args, **kwargs)
+                # set extra info on the module, in case we want it later
+                setattr(obj, '_original_path', path)
+                yield obj
 
 action_loader = PluginLoader(
     'ActionModule',

v2/ansible/plugins/callback/default.py

@@ -31,6 +31,7 @@ class CallbackModule(CallbackBase):
     '''
 
     CALLBACK_VERSION = 2.0
+    CALLBACK_TYPE = 'stdout'
 
     def v2_on_any(self, *args, **kwargs):
         pass

v2/ansible/plugins/callback/minimal.py

@@ -32,6 +32,7 @@ class CallbackModule(CallbackBase):
     '''
 
     CALLBACK_VERSION = 2.0
+    CALLBACK_TYPE = 'stdout'
 
     def v2_on_any(self, *args, **kwargs):
         pass