Implement a basic settings activity

TODO:
-remove extra reference files
-add actual preferences
Improved data organization, added "clear all" & "refresh" action buttons
-Click to remove field
-still much todo:
-add spinner for choosing quarter
-text field for year
-add button to modify courses under each year
-add button to "add" years
-long press to delete year?
-add textview on bottom to display current gpa
-etc....