Add updates about image responses, including screen shots

docs/en_us/course_authors/source/CreatePeerAssessment.rst

@@ -68,6 +68,7 @@ To allow students to submit an image with a response:
 
 .. note:: 
  
+   * The image file must be a .jpg or .png file, and it must be smaller than 5 MB in size.
    * Currently, course teams cannot see any of the images that students submit. Images are not visible in the body of the assignment in the courseware, and they are not included in the course data package.
    * You can allow students to upload an image, but you cannot require it.
    * Students can only submit one image with a response.

docs/en_us/course_authors/source/PeerAssessment.rst

@@ -47,6 +47,7 @@ The **prompt**, or question that you want your students to answer, appears near
    :width: 500
    :alt: ORA question and blank response field
 
+.. note:: If students upload an image, the image file must be a .jpg or .png file, and it must be smaller than 5 MB in size.
 
 When you write your question, you can include helpful information for your students, such as what students can expect after they submit responses and the approximate number of words or sentences that a student's response should have. (A response cannot have more than 10,000 words.) 
 

docs/en_us/course_authors/source/PeerAssessment_Students.rst

@@ -91,6 +91,8 @@ To upload your image:
 #. In the dialog box that opens, select the file that you want, and then click **Open**.
 #. When the dialog box closes, click **Upload Your Image**.
 
+..note:: The image file must be a .jpg or .png file, and it must be smaller than 5 MB in size.
+
 Your image appears below the response field, and the name of the image file appears next to the **Choose File** button. If you want to change the image, follow steps 1-3 again. You can only upload one image.
 
 .. image:: /Images/PA_Upload_WithImage.png