Tests:

    - Autogenerate and delete all test .fits files where possible.

Ideas / Other:

    - Residual Flux total, residual Flux Fraction, reduced Chi Squared, etc.


Major Refactor:

 - Extract geometry from mask, separately modules.
 - Move all _util to their packages, but keep util package for simple imports.
 - In the util functions dont use 1d / 2d for if a structure is len(shape) = 1 or 2, but use flat / another word.
 - Use 1D / 2D to refer to if the dimnesions of the data are 1D / 2D and rename all structures.
 - Decorator which automatically converts inputs from floats to tuples for 1D / 2D.