Common fixes:
- print function
- int / float division
- map, zip iterators in py3 but lists in py2

Known bugs with opencv 3.0.0
- digits.py, called via digits_video.py: https://github.com/Itseez/opencv/issues/4969
- gaussian_mix.py: https://github.com/Itseez/opencv/pull/4232
- video_v4l2.py: https://github.com/Itseez/opencv/pull/5474

Not working:
- letter_recog.py due to changed ml_StatModel.train() signature

Adding None as outImage in pos3 of cv2.drawKeypoints. Fixes bug that throws 'TypeError: Required argument 'outImage' (pos 3) not found' on left mouse button click

fixes for latest changes in opencv3.0 api

waitKey() normalization

fixed mser bindings

fixed find_obj.py

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

    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)

ASIFT

small fix in find_obj.py

- handle bad matching case
- use BFMatcher and FlannBasedMatcher (and thus fixing a bug: L2^2 metric was used for flann)

fixed "import cv" in the new python samples. corrected Python bindings to match the documentation and vice versa (NOTE: in cv2.stereoCalibrate the parameter ordering has been changed)