也就是find_package可以帮助直接找到库的头文件和库文件(.lib,dll .etc)
References:
http://blog.csdn.net/dbzhang800/article/details/6329314
http://blog.csdn.net/zxgis/article/details/7069596
http://blog.csdn.net/bowater/article/details/2477227
http://stackoverflow.com/questions/7902916/set-path-in-cmake-c-imagemagick
原文：http://www.cnblogs.com/foohack/p/3552430.html