Fixing the unrelated issue of correctly initializing the PRNG in our synthetic scene generator revealed issues with homography pose estimation. Out of the 4 decomposed solutions, the cheirality check can only eliminate 2 and we would randomly pick one of them. I added a reprojection check to resolve the ambiguity. This PR addresses both issues jointly. Previously, on synthetically generated image pairs, half of the pairs would fail to correctly estimate the relative pose from the homography. Now, we achieve 100% success rate. I also added more test coverage.