Mersenne Twister random number generator

The code is based on the official MT19937 implementation
It is fully rewritten:

http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html

todo: fixing copyright information

 c LEMON max flow problem

 p max 7 9

 n 1 s

 n 7 t

 a 1 2 3

 a 1 3 2

 a 1 4 1

 a 2 5 3

 a 3 5 2

 a 3 7 5

 a 3 6 3

 a 4 6 1

 a 5 7 2

 a 6 7 4