Add scaleVariance and op*=, etc. to regular BaseNoise
(#352)
Add unit tests for get/set/scaleVariance of regular BaseNoise
(#352)
Add tests of op*, op/ for BaseNoise
(#352)
Minor edits (typos, wording, etc.)
(#352)
Commit decimal_approx=3 so Barney can comment on whether I'm doing this right
(#352)