Add documentation

[ForNeVeR]

It would be very nice to provide some basic usage examples. While using the library (which is very good and solved my tasks) I was confused by multiple things:

1. Add behavior (already reported in #4 and #5).
2. Whether I need to call Balance() at all.
3. That I should declare my own instance for TypeMath<T> and whether I need to Register it or pass to KdTree constructor or both.

[codeandcats]

Agreed :+1:

[james-gould]

Has this been started? I can write up the documentation over the next few days when i have some free time.

[codeandcats]

Hi @james-gould, that would be greatly appreciated.

[james-gould]

Cool, I'm still tinkering with it at work so I'll more than likely add the docs next weekend.

[KingKnecht]

Any news on this? Would be really helpful to know how to use this package.

[RobThree]

#17 now provides a (very basic) example. Not closing since a lot more/better is needed.

[stephanmg]

Btw.: You write fast, do you have any benchmark to confirm this? And what do you mean by fast (Which operations)?