Remove old code in Gradebook.coffee

The removed code was first removed here:
instructure/canvas-lms @ a51385bc02edcaf5540a85825abd547af485c70c
Fix partially blocked SFU Canvas logo
Alphabetize course drop-down list (Import Content)
Merge pull request #143 from va7map/misc-2014-01-31

Fix blocked logo + alphabetize course drop-down list
Merge pull request #142 from va7map/canvas188-sort_fix-2

Remove old code in Gradebook.coffee
Modify the test cluster plugin to allow whitelisted users to bypass the
student lockout

add a REST.text method to handle making non-JSON calls to AOBRestServer

Add the maillist_membership URL to the SFU API

add a SFU::User::maillist method to the SFU API

Modify test cluster plugin to allow whitelisted users to bypass the student lockout
Merge pull request #144 from grahamb/testcluster

Modify the test cluster plugin to allow whitelisted users to bypass the student lockout
Fix inability to re-create deleted course

The API was including deleted courses before, so the form was stopping
anyone from re-creating a deleted course with the same SIS ID.
Merge pull request #145 from va7map/fix-recreate_deleted_course

Fix inability to re-create deleted course