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.
Ok, I'm gonna come clean - I have no idea. I found a few versions of this algorithm in JavaScript and C and ported it over. But after about two hours of looking around, I have yet to find a good explaination of how it works. The variable names are consistent with the different versions I've seen, but I agree that they are not meaningful. I'm not sure how to proceed and I'm open to suggestions.