reorders lines in a file in semirandom ways

 This program reorders the lines in its input with no regard to the actual
 contents. Two permutation algorithms are available: randomization
 based on a good PRNG (the Mersenne Twister algorithm) and "shuffling",
 which permutes the lines in such a way that they're spread more or less
 evenly in the output. This mode is primarily intended for music playlists.