Empty template now recognized as allowing markdown editing

Save saves markdown and updates the xml

cms/static/coffee/src/views/module_edit.coffee

@@ -55,7 +55,7 @@ class CMS.Views.ModuleEdit extends Backbone.View
   clickSaveButton: (event) =>
     event.preventDefault()
     data = @module.save()
-    data.metadata = @metadata()
+    data.metadata = _.extend(data.metadata, @metadata())
     $modalCover.hide()
     @model.save(data).done( =>
     #   # showToastMessage("Your changes have been saved.", null, 3)

cms/templates/widgets/problem-edit.html

 <%include file="metadata-edit.html" />
 <section class="problem-editor editor">
     <div class="row">
-        %if markdown != '' or data == '':
+        %if markdown != '' or data == '<problem>\n</problem>\n':
         <div class="editor-bar">
             <ul class="format-buttons">
                 <li><a href="#" class="multiple-choice-button" data-tooltip="Multiple Choice"><span

common/lib/xmodule/xmodule/js/src/problem/edit.coffee

@@ -61,7 +61,15 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
   save: ->
     $body.off('click', '.editor-tabs .tab', @changeEditor)
     $body.off('click', '.editor-bar a', @onToolbarButton);
-    data: @xml_editor.getValue()
+    # TODO when logic is in place to remove the markdown if xml is edited, ensure this doesn't overwrite that
+    if @current_editor == @markdown_editor
+        {
+            data: MarkdownEditingDescriptor.markdownToXml(@markdown_editor.getValue())
+            metadata: 
+            	markdown: @markdown_editor.getValue()
+        }
+    else 
+        data: @xml_editor.getValue()
 
   @insertMultipleChoice: (selectedText) ->
     return MarkdownEditingDescriptor.insertGenericChoice(selectedText, '(', ')', MarkdownEditingDescriptor.multipleChoiceTemplate)