converted necessary files for python3 compatibility using 2to3
fixed relative imports in Jinja for python3
explicit string encoding when writing to file in python3
added epsilon value to weights in the MergeMertens in order to avoid zero weights for pixels from uniformly filled areas of image
added test for correct handling of uniforma areas in the MergeMertens
Merged upstream master
modified OpenCL SURF API and the tests in 2.4.x to prove that it gives different from CPU results
made SURF_OCL default constructor parameters the same as SURF
modified SURF's performance test to test OpenCL version as well
fixed doc builder warnings; make sure the tests give reasonable results when OpenCL is not available
Fix for bug #3599: cv::FileStorage does not work for std::vector of user-defined struct.
made the example consistent with the fuction definition and improved doc

made the example consistent with the fuction definition and improved doc
WriteStructContext treats state of fs
1. fix an error in sample code
2. change an external link to maintain consistency with the previous tutorial
remove highlighting in some function links

1. Remove whole-document highlighting in some function links
2. fix the function alias `readwriteimagevideo`
added gpu type selection in OPENCV_OPENCL_DEVICE parser
Added test code for I/O of user-defined types.
Fixed Load, Modify, and Save an Image tutorial
Keep definitions of link aliases consistent
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