Boggle Assignment

Runs a game of Boggle on a GUI that can be played by the user against a computer opponent.
The board is randomly generated, and the compute rcan play in one of two ways:
the "lexicon first" method recurses across the board for each word in the given lexicon to
check if it is on the board, and the "board first" method covers the board with recursive
backtracking to see if its progress constitutes a prefix or a word in the lexicon.