Updating STAR detector and FREAK descriptor to work with large and/or 16-bit images
Don't automatically convert to grayscale (keep previous behavior.)
Merge branch 'master' of https://github.com/Itseez/opencv

Conflicts:
	modules/imgproc/src/sumpixels.cpp
Add a new method for initializing KMeans centers that leads to better clusters and thus better retrieval when final centers have to be existing keypoints instead of clusters barycenters.
Do not build apple objective-c codes if using gcc
Merge branch 'master' of https://github.com/Itseez/opencv

Conflicts:
	modules/features2d/include/opencv2/features2d.hpp
	modules/features2d/src/freak.cpp
	modules/features2d/src/stardetector.cpp
ocl_calcOpticalFlowPyrLK optimizations

1. decrease branch number in CL code by replacing them into weights
2. decrease local mem pressure in reduce operation by using private variables
3. decrease image sampler pressure by caching data into local memory
4. remove unnecessary sync point on the HOST side.
Merge remote-tracking branch 'github/master' into pullreq/140319-PyrLKOpticalFlow

Conflicts:
	modules/video/src/opencl/pyrlk.cl
fix previous merge error
cv::norm -> cvtest::norm in tests

Conflicts:

	modules/core/src/stat.cpp
fixed slow down in getRectSubPix (original patch by Markus JR Mueller); removed some unused variables and functions
Merge pull request #2566 from krodyush:pullreq/140319-PyrLKOpticalFlow
Merge pull request #2585 from ilya-lavrenov:norm
disabled some IPP funcs
cv::warpPerspective and cv::warpAffine
cv::transpose
cv::polarToCart
cv::accumulateWeighted
cv::accumulateSquare && cv::acumulateProduct
cv::sqrt