started setting up new interpolater class.

Made some test changes to linear interpolaters, but did not wind up saving any changes.
added files
Scale inputs + tests
Removed find nearest point from linear.pyx

This should not be needed now that I am using the scaling logic. It was a bad idea in the first place.
Refactored linear.pyx to use pure c function exposed through python wrappers.

Also removed dependeancy on nearest point from RectangularRegion. It still needs to be removed from its code, but this will be refactored into thew interpolate class soon anyways
Added function to interpolate many linear points and a simple test.

Still need to add bilinear, which should be fairly easy.
Changed .gitignore to allow ipython notebooks.

I am using them to develope the numerical portions of my code, this will make it easier to share between my computers.
Added bilinear interpolation function for many points and a simple test
Added interpolation to Interpolater.

Currently it is hardcoded to use InterpolatePointsBilinear, this should be easy to back out eventually. Since I am doing everything in 2d for now I am not concerned with making it any more general.
Added very basic getitem support to interpolater.

Still need to add error checks on the slices
Updated interpolation in RectangularRegion to use the Interpolater class.

Also did some cleanup in Interpolater.
Closes #7