Adding DavidTest code
Merge pull request #2 from dpuelz/DavidAR1Test

Hey man, I've branched from your Test Branch and added a test code - check it out
OLS

I add OLS estimations of a, b and sigmabeta2. I think we should look at
these numbers instead of the true value.
Merge pull request #7 from mathsoul/TestBranch

OLS estimations