Change output format

Now returns results as a ruby object (array of hashes) instead of JSON.

Add BSD 3-Clause License and move to AgRuby

v0.3.0

Version 0.3.0

Adds additional solar radiation parameters

Output now also includes:

• rad_atmosphere: Average Top-of-atmosphere Insolation (MJ/m^2/day)
• rad_flux: Average Downward Longwave Radiative Flux (MJ/m^2/day)

Initial Release

Fetch year(s) of solar radiation data (insolation on horizontal surface) for a given latitude, longitude between start year and end year.