Integration of astropy.units in sunpy codebase

Attempt to integrate the astropy.units into sunpy. Every function that were taking or giving a quantity now must have astropy quantity associated with them. Please tell me if I have made mistakes anywhere, or if it could be done in better way, I will make changes! 
Thank you!   
Yea, I found out about them today. I am done with `vso/attrs.py` but there files which are in turn dependent on `attrs.py` more specifically on `Wave` class. I have to change the rest now.