Fixed to work with OpenCV-2.4.9

I simply updated all the files by copying the latest versions from OpenCV-2.4.9. I also modified the make file to only compile for only armeabi-v7a because most modern devices support it.

I didn't include the OCL code as suggested by the tutorial here: http://web.guohuiwang.com/technical-notes/sift_surf_opencv_android