Fixed a potential bug in the guessing algorithm, which would occur when there are no cells to make a guess off of, but guesses can still be made. In this situation, it would go with the first possible cell to guess off of, as they all have a 0.0 chance of guessing correctly. Thus, I changed all cells that cannot be guessed off of to -1.0, and the unknown cells have a 0.0 chance. If there are no other possible cells that can be guessed off of, then it just goes to an unknown cell and guesses on it, given that all mines have not been found. Also made it so that it only finds the positioning of the grid on the screen once, as it would sometimes click off screen by accident and I think that it may be due to it running the position finding algorithm in an intermediate screenshot where a popup is beginning to appear and the colours are not as they should be. There was no reason to find the coordinates multiple times as well, and it is faster as a result.