Documentation not clear

[tejus-gupta]

First of all, thank you for the nice package.

For this issue, I wanted to point out that the meaning of board_width and board_height parameters for intrinsic calibration aren't clear.

./calibrate -w [board_width] -h [board_height] -n [num_imgs] -s [square_size] -d [imgs_directory] -i [imgs_filename] -o [file_extension] -e [output_filename]

board_height and board_width should be the number of inner corners per row or column (see documentation for findChessboardCorners).
e.g, If I am using a 10x8 checker board, I should use board_height=9 and board_width=7 but the the above instructions asks me to use board_height=10 and board_width=8.