Add Root and RootRound methods

[mediocregopher]

For computing the arbitrary nth root of any number. I also go formatted some unrelated bits of code.

I implemented the shifting nth root algorithm in order to compute an nth root to an arbitrary precision. Other methods, such as Newton's method, are potentially faster but involve some amount of uncertainty as they only give an approximation, while shifting nth root gives the precise answer. Also, a slow method is better than no method :P

[mwoss]

Sorry for the late response, really late response :D
I like your implementation, it's quite clear and understandable. Also, those unit tests are implemented quite well too imo :3!
One thing, I've noticed this implementation is only working on integers, it's not ideal, but I think it is fine as long it is documented tho. I will try to come up with a more flexible solution, but for now, let's go with your solution. Could you rebase to master? :3

[mediocregopher]

Hi @mwoss , thanks for taking a look at the PR :) I will try to find time one of these days to clean it up as you ask but tbh it may be a while. It might be faster for you to simply take over the the PR or open a new one (I don't really care if I get contributor credit or not).

[mwoss]

Sure, I can do it myself too. For sure I will at least put your GH nickname in the changelog, as I really appreciate your contribution to this library :3