Merge pull request #3279 from edx/max/more-xqwatcher

Update xqwatcher docker overrides to new format from 6fc28e55

docker/build/xqwatcher/ansible_overrides.yml

@@ -16,10 +16,12 @@ XQWATCHER_COURSES:
         - HANDLER: "xqueue_watcher.jailedgrader.JailedGrader"
           CODEJAIL:
             name: "demo"
-            python_bin: "{{ xqwatcher_venv_base }}/demo/bin/python"
+            bin_path: "{{ xqwatcher_venv_base }}/demo/bin/python"
             user: "demo"
+            lang: python2
           KWARGS:
             grader_root: "../data/edx-demo-course/graders/"
     PYTHON_REQUIREMENTS:
       - { name: "numpy", version: "1.6.2" }
       - { name: "lxml", version: "2.3.6" }
+    PYTHON_EXECUTABLE: python2