Merge pull request #4242 from edx/ahodges/documentation/DOC367

PR 2571, log stop_video event

docs/en_us/data/source/internal_data_formats/change_log.rst

@@ -14,6 +14,8 @@ Change Log
    * - 06/27/14
      - Made a correction to the ``edx.forum.searched`` event name in the
        :ref:`Tracking Logs` chapter.
+   * - 
+     - Added the ``stop_video`` event to the :ref:`Tracking Logs` chapter.
    * - 06/23/14
      - Added a :ref:`Preface` with resources for course teams, developers, researchers, and students. 
    * - 05/23/14

docs/en_us/data/source/internal_data_formats/tracking_logs.rst

@@ -540,9 +540,12 @@ The browser emits these events when a user works with a video.
 ``play_video``, ``pause_video``
 ---------------------------------
 
-* The browser emits ``play_video`` events on video play. 
+* The browser emits ``play_video`` events when the user clicks the video
+  **play** control.
 
-* The browser emits  ``pause_video`` events on video pause. 
+* The browser emits  ``pause_video`` events when the user clicks the video
+  **pause** control. The browser also emits these events when the video player
+  reaches the end of the video file and play automatically stops.
 
 ``event`` **Member Fields**: These events have the same ``event`` fields.
 
@@ -567,6 +570,27 @@ The browser emits these events when a user works with a video.
      - string
      - Video speed in use: '0.75', '1.0', '1.25', '1.50'.
 
+``stop_video``
+--------------------
+
+The browser emits  ``stop_video`` events when the video player reaches the end
+of the video file and play automatically stops.
+
+**History**: Added 25 June 2014.
+
+``event`` **Member Fields**: 
+
+.. list-table::
+   :widths: 15 15 60
+   :header-rows: 1
+
+   * - Field
+     - Type
+     - Details
+   * - ``currentTime``
+     - float
+     - Time the video ended, in seconds. 
+
 ``seek_video``
 -----------------