Paper: Measuring rainshafts: Bringing python to bear on remote sensing data. (Collis et al)

First full draft.. probably needs a good edit.. But ready for initial review. 
Expanded on indirect, ie not in-situ
Changed geospatially geometrically.. 
Kept media in there but added "eg: raindrops" Fact is with radars you never quite know *what* you are scattering off.. Could be clouds and ice.. could be birds, dust, buildings, planes.. that is the fun of it :)