noiseSeed(), randomSeed(), randomGaussian()

This pull request includes an LCG (http://en.wikipedia.org/wiki/Linear_congruential_generator) for seeding random numbers and perlin noise values.  I also implemented `randomGaussian()` using [Box Muller](http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform).  I guess we'll need unit tests for these as well.