ENH: Radar colormaps

Colormaps which are aimed at Radar moments.

These colormaps were taken from the Deprecated_Matpy project:
https://github.com/pmarshwx/Deprecated_Metpy
https://github.com/pmarshwx/Deprecated_Metpy/blob/master/metpy/vis/ctables.py

Code for converting the color tuples to matplotlib colormaps taken from
the matplotlib project:
http://matplotlib.org/
https://github.com/matplotlib/matplotlib/blob/master/lib/matplotlib/cm.py
Merge pull request #84 from jjhelmus/master

ENH: Radar colormaps