- Added author provided fixes
- Added code example
- Added documentation fixes

Conflicts:
	modules/core/include/opencv2/core/cuda.hpp
	modules/cudacodec/src/thread.cpp
	modules/cudacodec/src/thread.hpp
	modules/superres/perf/perf_superres.cpp
	modules/superres/src/btv_l1_cuda.cpp
	modules/superres/src/optical_flow.cpp
	modules/videostab/src/global_motion.cpp
	modules/videostab/src/inpainting.cpp
	samples/cpp/stitching_detailed.cpp
	samples/cpp/videostab.cpp
	samples/gpu/stereo_multi.cpp

Usage:

import numpy as np
import cv2
img = cv2.imread('messi5.jpg',0)
sift = cv2.SIFT()
kp = sift.detect(img)

pts = cv2.KeyPoint_convert(kp)

kps = cv2.KeyPoint_convert(pts.reshape(-1,1,2))

overlap = cv2.KeyPoint_overlap(kp[0],kp[1])

ReST directive was used. Also fixed some other ReST directives that were
not correct and removed some warnings during buildbot checks.

- Used lunix style slashes - works on most systems
- Removed all trailing whitespaces

setMouseCallback
createTrackbar

removed separate example for reading image sequences and modified starter_video.cpp to better explain the functionality of VideoCapture. I also added a bit more explanation in the documentation of the VideoCapture interface

+ Some minor formatting fixes.