New trigonometric and hyperbolic functions

[ephod]

Dear MarkBaker, I would like to contribute to your project by adding several new methods to your project.

The Haversine, as well as, the Gudermannian functions with their respective inversive functions have been added.

The Unity Tests have not been done yet. Due to the lack of knowledge I'll have to practice a wee more.

Regards, Michael A. Johnson

[MarkBaker]

Sorry I've not had a chance to look at this PR so far: I've been rather distracted with other matters over the last month.

As you may have seen, I've already implemented the remaining trig functions (though I will have a look at your implementation to see if it's more efficient than my own), and I'll certainly take a look at the other functions