Added a plethora of methods - elo rankings, win %

added
-retrieving stats page of all dream casts
-saving stats to file
-find_matches(): searching for matches fought between 2 contestants
given by user input from stats file
-printing all matches played by any given contestants and their
calculated winrates, and respective Elo ratings
-calculation of Elo ratings for each contestant, and saving the ratings
to a file.
-a function that prints out all Elo ratings from the file
-a function that returns a given contestant's Elo rating