Add failing tests highlighting the problem

Note that the failure of the randn part is due to issue
torch/torch7-distro#191
Add test for setting with wrong state
Wrap torch.randomSeed and .[gs]etRNGState
Merge pull request #21 from jucor/seed

Extend torch.manualSeed(), getRNGState(), and setRNGState()
Document seed
Merge branch 'master' into gh-pages