Cleaned up the UI ALOT. Finally learned GridBagLayout because GridLayout just wasn't cutting it. Moved the callback interface for the enroll course dialog into the enroll course dialog rather than being in the CourseListViewController. I figured because the EnrollCourseDialog is the one that calls the callback, it should be the one to define the interface for it. I also made a new class, the AreYouSureDialog, which prompts a user to confirm an action. Right now its being used to confirm that a user wants their schedule cleared when they hit the clear button, but it should be able to be used for any other parts of this project that need confirmation. Similar to the Enroll dialog, it has a callback interface. It will call an implementing class method when the user selects yes.