json-c downloads have moved to Amazon S3 (see https://github.com/json-c/json-c/issues/72)
Merge pull request #160 from residuum/master

Official json-c downloads have moved
add package opencv

OpenCV (Open Source Computer Vision Library) is an open source computer vision and machine learning software library.

See more: http://opencv.org/about.html
Merge pull request #164 from lsaavedr/add_opencv

add package opencv