Cast arg as string in trim() and split()
Misc cleanup
T S2: fixed some indent to shut wmlindent up
T S1: preliminary reduction of 'hand holding'
T S1: removed some unused local macros, and expanded others that were used once
T S1: simplified variable character placement
T S1: dropped the now-useless catch-all undo event
T S1: fixed an on -> in screwup of mine
T S1: dropped the now-unused 'student' var
T S1: clear student_store after use
T S1: made sure Li'sar is facing correctly
T S1: dropped wmllint: no-syntax-rewrite comment
T: moved CONTINUE_MSG to utils