How to disable the randomness of CP generation ?

[bastien lee]

I want to make the control points generation be deterministic every time, that is to say, the number, coordinate and matching of control points should be same evey time.

I found one of the random source is `srandom((unsigned int)time(NULL));` in `void PanoDetector::run()`, so I change it to `srandom(0);`, but I found the results of two times are still different.

I guess the remaining randomness comes from `MatchDataRunnable`, but I don't know eactly where