WL-98 As a course instructor, auto-register (as well as auto enroll) a list of students into my course

@chrisndodge here are the changes related to WL-98 for your quick reivew. 
we have written the test cases but only one coverage is missing in our code.  
currently we did not check/test the code for quality.

In order to test this feature you need to set the flag: 
FEATURES['ALLOW_AUTOMATED_SIGNEDUPS'] = True
If you aren't going to use the "with" syntax that closes the file and handles any errors that are thrown, you need to put the close of the file in a try-finally clause so it is closed in the event of an error being thrown. Also, for code clarity close the file in proximity to where you are using it (instead of end of "if" clause).