drag_and_drop template added

common/lib/xmodule/xmodule/templates/problem/drag_and_drop.yaml

+---
+metadata:
+    display_name: Drag and Drop
+    rerandomize: never
+    showanswer: finished
+data: |
+    <problem>
+        Here's an example of a "Drag and Drop" question set. Click and drag each word in the scrollbar below, up to the numbered bucket which matches the number of letters in the word. 
+       <customresponse>
+            <drag_and_drop_input img="https://studio.edx.org/c4x/edX/DemoX/asset/L9_buckets.png">
+                <draggable id="1" label="a"/>
+                <draggable id="2" label="cat"/>
+                <draggable id="3" label="there"/>
+                <draggable id="4" label="pear"/>
+                <draggable id="5" label="kitty"/>
+                <draggable id="6" label="in"/>
+                <draggable id="7" label="them"/>
+                <draggable id="8" label="za"/>
+                <draggable id="9" label="dog"/>
+                <draggable id="10" label="slate"/>
+                <draggable id="11" label="few"/>
+            </drag_and_drop_input>
+            <answer type="loncapa/python">
+            correct_answer = {
+                    '1':      [[70, 150], 121],
+                    '6':      [[190, 150], 121],
+                    '8':      [[190, 150], 121],
+                    '2':      [[310, 150], 121],
+                    '9':      [[310, 150], 121],
+                    '11':     [[310, 150], 121],
+                    '4':      [[420, 150], 121],
+                    '7':      [[420, 150], 121],
+                    '3':      [[550, 150], 121],
+                    '5':      [[550, 150], 121],
+                    '10':     [[550, 150], 121]}
+            if draganddrop.grade(submission[0], correct_answer):
+                correct = ['correct']
+            else:
+                correct = ['incorrect']
+            </answer>
+        </customresponse>
+    </problem>
+
+children: []