sunpy/sunpy — pull request #522 by derdon (2013-08-01 20:16:40+00:00)
Title: new function extract_waveunit in module io.fits

I added the function ``extract_waveunit`` so that one can find out which unit was used to measure the wavelengths. As always, this PR is of course open for discussion and not final in any way.

PS: I included the commits by Cadair because they are necessary for making the tests pass. If this makes the merging process to messy, I can exclude them again.