Also, removed the one from modules/python/src2/cv.py and cleared its
executable bit, since it's not a script.

houghlines.py for HoughLinesP() and HoughLines()
houghcircles.py for HoughCircles()

This makes arguments of type InputOutputArray required in python unless they
have a default value in C++.

As result following python functions changes signatures in non-trivial way:

* calcOpticalFlowFarneback
* calcOpticalFlowPyrLK
* calibrateCamera
* findContours
* findTransformECC
* floodFill
* kmeans
* PCACompute
* stereoCalibrate

And the following functions become return their modified inputs as a return
value:

* accumulate
* accumulateProduct
* accumulateSquare
* accumulateWeighted
* circle
* completeSymm
* cornerSubPix
* drawChessboardCorners
* drawContours
* drawDataMatrixCodes
* ellipse
* fillConvexPoly
* fillPoly
* filterSpeckles
* grabCut
* insertChannel
* line
* patchNaNs
* polylines
* randn
* randShuffle
* randu
* rectangle
* setIdentity
* updateMotionHistory
* validateDisparity
* watershed

    Update find_obj.py:
    Added additional error checking for the loaded files and modified the detector check to be more pythonic (is versus ==).

    Update common.py:
    Fixed a typo (contais -> contains)

range in calcHist() changed from [0,255] to [0,256]. Otherwise, it won't count pixels with value 255. It can be verified taking sum of histogram values and checking it with image size.

added some sample description

Bug #2257: Adding a quick workaround for truncated labels on 64bit machines in the Python FaceRecognizer wrapper code. This is only a temporary bugfix, that will be fixed at a better point as soon as possible.

rewritten feature_homography.py using it
added plane_ar.py - simple augmented reality sample

building descriptor index on target capture
simple AR experiment (work in progress)

ASIFT

ASIFT