(WIP) 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
We don't want more CoffeeScript. All new features should be written in JavaScript (as an example, see the cohort JS files that are used in the instructor dashboard).

@chrisndodge Please communicate with the folks working with Solutions and Professional Ed that they should not write features in CoffeeScript going forward.