Register block_structure djangoapp.

TNL-5274

cms/envs/common.py

@@ -876,7 +876,8 @@ INSTALLED_APPS = (
     'edx_jsme',    # Molecular Structure
 
     'openedx.core.djangoapps.content.course_overviews',
-    'openedx.core.djangoapps.content.course_structures',
+    'openedx.core.djangoapps.content.course_structures.apps.CourseStructuresConfig',
+    'openedx.core.djangoapps.content.block_structure.apps.BlockStructureConfig',
 
     # Credit courses
     'openedx.core.djangoapps.credit',

lms/envs/common.py

@@ -2033,7 +2033,8 @@ INSTALLED_APPS = (
 
     # Course data caching
     'openedx.core.djangoapps.content.course_overviews',
-    'openedx.core.djangoapps.content.course_structures',
+    'openedx.core.djangoapps.content.course_structures.apps.CourseStructuresConfig',
+    'openedx.core.djangoapps.content.block_structure.apps.BlockStructureConfig',
     'lms.djangoapps.course_blocks',
 
     # Old course structure API

openedx/core/djangoapps/content/__init__.py

-"""
-Setup the signals on startup.
-"""
-import openedx.core.djangoapps.content.course_structures.signals
-import openedx.core.djangoapps.content.block_structure.signals

openedx/core/djangoapps/content/block_structure/apps.py

+"""
+Configuration for block_structure djangoapp
+"""
+
+from django.apps import AppConfig
+
+
+class BlockStructureConfig(AppConfig):
+    """
+    block_structure django app.
+    """
+    name = u'openedx.core.djangoapps.content.block_structure'
+
+    def ready(self):
+        """
+        Define tasks to perform at app loading time
+
+        * Connect signal handlers
+        * Register celery tasks
+
+        These happen at import time.  Hence the unused imports
+        """
+        from . import signals, tasks  # pylint: disable=unused-variable

openedx/core/djangoapps/content/course_structures/apps.py

+"""
+Django Application Configuration for course_structures app.
+"""
+from django.apps import AppConfig
+
+
+class CourseStructuresConfig(AppConfig):
+    """
+    Custom AppConfig for openedx.core.djangoapps.content.course_structures
+    """
+    name = u'openedx.core.djangoapps.content.course_structures'
+
+    def ready(self):
+        """
+        Define tasks to perform at app loading time:
+
+        * Connect signal handlers
+        """
+        from . import signals  # pylint: disable=unused-variable