remove imaginary from type.complex.sdk, part of issue #450
imaginary stripped from type.complex.base
imaginary stripped from type.complex.trigonometric
imaginary stripped from type.complex.exponential
imaginary completely stripped from type.complex
Merge pull request #479 from MetaScale/remove_imaginary

Remove imaginary. Imaginary numbers need to decay to complex numbers most of the time, so the extra specializations are not worth it. Fix issue #450.