Added note-taking

gui_terminal.py
;    Adjusted text to fit without horizontal scrolling
;    Board is no longer reprinted before the end of each loop
;    Implemented note-taking
flip.py
;    Adjusted docstrings to fit without horizontal scrolling
;    note() checks for string input, not int
;    note()'s error-checking is more precise/helpful
score_combos.txt
;    Don't worry about this, just some personal notes about the score of
a board