Students T-Test

Added functions for Students T-Test one sample and independant sets and a function to convert a t-value to a p-value. Not sure about the naming, if you would like me to change the function names and resubmit requrest, let me know. I have tests, I will add examples next week and I would like to add dependant sets after that.
It's all religion really, but it's nice to use the var label that is in the format string, and got is nice and short. If I had my voyage again, I would have done a lot of my old code very differently. I think rsc and others chose want for shortness and clarity.