Simplify hack to obtain waffle module names

Instead of going up the stacktrace to find the module names of waffle
flags and switches, we manually pass the module __name__ whenever the
flag is created. This is similar to `logging.getLogger(__name__)`
standard behaviour.

As the waffle classes are used outside of edx-platform, we make the new
module_name argument an optional keyword argument. This will change once
we pull waffle_utils outside of edx-platform.

Note that the module name is normally only required to view the list of
existing waffle flags and switches. The module name should not be
necessary to verify if a flag is enabled. Thus, maybe it would make
sense to create a `add` class methor similar to:

    class WaffleFlag:
        @classmethod
        def add(cls, namespace, flag, module):
            instance = cls(namespace, flag)
            cls._class_instances.add((instance, module))

cms/djangoapps/contentstore/config/waffle.py

@@ -36,11 +36,13 @@ def waffle_flags():
 ENABLE_CHECKLISTS_QUALITY = CourseWaffleFlag(
     waffle_namespace=waffle_flags(),
     flag_name=u'enable_checklists_quality',
+    module_name=__name__,
 )
 
 SHOW_REVIEW_RULES_FLAG = CourseWaffleFlag(
     waffle_namespace=waffle_flags(),
     flag_name=u'show_review_rules',
+    module_name=__name__,
 )
 
 # Waffle flag to redirect to the library authoring MFE.
@@ -58,4 +60,5 @@ SHOW_REVIEW_RULES_FLAG = CourseWaffleFlag(
 REDIRECT_TO_LIBRARY_AUTHORING_MICROFRONTEND = WaffleFlag(
     waffle_namespace=waffle_flags(),
     flag_name='library_authoring_mfe',
+    module_name=__name__,
 )

cms/djangoapps/contentstore/views/item.py

@@ -90,7 +90,7 @@ NEVER = lambda x: False
 ALWAYS = lambda x: True
 
 
-highlights_setting = WaffleSwitch(u'dynamic_pacing', u'studio_course_update')
+highlights_setting = WaffleSwitch('dynamic_pacing', 'studio_course_update', __name__)
 
 
 def _filter_entrance_exam_grader(graders):

cms/djangoapps/contentstore/views/videos.py

@@ -81,6 +81,7 @@ WAFFLE_STUDIO_FLAG_NAMESPACE = WaffleFlagNamespace(name=u'studio')
 ENABLE_VIDEO_UPLOAD_PAGINATION = CourseWaffleFlag(
     waffle_namespace=WAFFLE_STUDIO_FLAG_NAMESPACE,
     flag_name=u'enable_video_upload_pagination',
+    module_name=__name__,
 )
 # Default expiration, in seconds, of one-time URLs used for uploading videos.
 KEY_EXPIRATION_IN_SECONDS = 86400

cms/djangoapps/models/settings/waffle.py

@@ -12,6 +12,7 @@ MATERIAL_RECOMPUTE_ONLY = 'MATERIAL_RECOMPUTE_ONLY'
 MATERIAL_RECOMPUTE_ONLY_FLAG = CourseWaffleFlag(
     waffle_namespace=WAFFLE_NAMESPACE,
     flag_name=MATERIAL_RECOMPUTE_ONLY,
+    module_name=__name__,
 )