Add sequence and vertical js modules that add drag and drop

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

+class @SequenceDescriptor
+  constructor: (@element) ->
+    @$tabs = $(@element).find("#sequence-list")
+    @$tabs.sortable()

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

+class @VerticalDescriptor
+  constructor: (@element) ->
+    @$items = $(@element).find(".vert-mod")
+    @$items.sortable()

common/lib/xmodule/xmodule/seq_module.py

@@ -119,6 +119,9 @@ class SequenceDescriptor(MakoModuleDescriptor, XmlDescriptor):
 
     template_dir_name = 'sequence'
 
+    js = {'coffee': [resource_string(__name__, 'js/src/sequence/edit.coffee')]}
+    js_module_name = "SequenceDescriptor"
+
     @classmethod
     def definition_from_xml(cls, xml_object, system):
         children = []

common/lib/xmodule/xmodule/vertical_module.py

 from xmodule.x_module import XModule
 from xmodule.seq_module import SequenceDescriptor
 from xmodule.progress import Progress
+from pkg_resources import resource_string
 
 # HACK: This shouldn't be hard-coded to two types
 # OBSOLETE: This obsoletes 'type'
@@ -40,3 +41,6 @@ class VerticalModule(XModule):
 
 class VerticalDescriptor(SequenceDescriptor):
     module_class = VerticalModule
+
+    js = {'coffee': [resource_string(__name__, 'js/src/vertical/edit.coffee')]}
+    js_module_name = "VerticalDescriptor"