Added video, ground truth and sanity data for tracking module

Added testdata david, dudek and faceocc2 for test and perf_test of tracking module
See https://github.com/Itseez/opencv_contrib/pull/4

All image files and ground truth are taken from [1] with the agreement of the authors.
The original sequences of images are combined in video files.

[1] Wu, Yi, Jongwoo Lim, and Ming-Hsuan Yang. "Online Object Tracking: A Benchmark." in Computer Vision and Pattern Recognition (CVPR), 2013 IEEE Conference on. IEEE, 2013.