Make the simple course pass roundtrip test:

- add 'type' and 'points' to capa_module metadata
- replace old 'title' tag with display_name

common/lib/xmodule/xmodule/capa_module.py

@@ -563,6 +563,11 @@ class CapaDescriptor(RawDescriptor):
 
     module_class = CapaModule
 
+    # Capa modules have some additional metadata:
+    # TODO (vshnayder): do problems have any other metadata?  Do they
+    # actually use type and points?
+    metadata_attributes = RawDescriptor.metadata_attributes + ('type', 'points')
+
     # VS[compat]
     # TODO (cpennington): Delete this method once all fall 2012 course are being
     # edited in the cms

common/lib/xmodule/xmodule/tests/test_export.py

@@ -93,6 +93,8 @@ class RoundTripTestCase(unittest.TestCase):
     def test_toy_roundtrip(self):
         self.check_export_roundtrip(DATA_DIR, "toy")
 
+    def test_simple_roundtrip(self):
+        self.check_export_roundtrip(DATA_DIR, "simple")
 
     def test_full_roundtrip(self):
         self.check_export_roundtrip(DATA_DIR, "full")

common/test/data/simple/course.xml

@@ -15,7 +15,7 @@
   <chapter name="Chapter 2">
     <section name="Problem Set 1">
       <sequential>
-        <problem type="lecture" showanswer="attempted" rerandomize="true" title="A simple coding problem" name="Simple coding problem" filename="ps01-simple"/>
+        <problem type="lecture" showanswer="attempted" rerandomize="true" display_name="A simple coding problem" name="Simple coding problem" filename="ps01-simple"/>
       </sequential>
     </section>
     <video name="Lost Video" youtube="1.0:TBvX7HzxexQ"/>