Add logging when info and about sections are missing

common/lib/xmodule/xmodule/course_module.py

+import logging
 from path import path
 from xmodule.modulestore import Location
 from xmodule.seq_module import SequenceDescriptor, SequenceModule
 from fs.errors import ResourceNotFoundError
 
+log = logging.getLogger(__name__)
+
+
 class CourseDescriptor(SequenceDescriptor):
     module_class = SequenceModule
 
@@ -53,6 +57,7 @@ class CourseDescriptor(SequenceDescriptor):
                 with self.system.resources_fs.open(path("about") / section_key + ".html") as htmlFile:
                     return htmlFile.read()
             except ResourceNotFoundError:
+                log.exception("Missing about section {key} in course {url}".format(key=section_key, url=self.location.url()))
                 return "! About section missing !"
         elif section_key == "title":
             return self.metadata.get('display_name', self.name)
@@ -81,6 +86,7 @@ class CourseDescriptor(SequenceDescriptor):
                 with self.system.resources_fs.open(path("info") / section_key + ".html") as htmlFile:
                     return htmlFile.read()
             except ResourceNotFoundError:
+                log.exception("Missing info section {key} in course {url}".format(key=section_key, url=self.location.url()))
                 return "! About section missing !"
 
         raise KeyError("Invalid about key " + str(section_key))