WIP: Fixing spectrogram quantities to make CALLISTO docs examples to work

@kaichogami, @cadair these are some changes I'm making to your PR sunpy/sunpy#1079 

For now I'm just step-by-step I'm finding out where [CALLISTO examples](https://sunpy.readthedocs.org/en/latest/guide/data_types/spectra.html#spectrograms) fails.

Do not merge yet.  Few things need to be checked/modified
 - [ ] All examples work
 - [ ] Documentation is updated
 - [ ] Everything makes sense (well.. probably just to @segfaulthunter)