See also #2101

Fixed a valgrind 'Conditional jump or move depends on uninitialised value(s)' on cv::kmeans(...). The original code used points(sampleCount, 1, CV_32FC2), which confused generateCentersPP into thinking it is a 1 dimensional center, instead of 2. As a result it would set only the x variable and leave y unitialised.

Fix compilation erros when compiling this constructor.
First argument type of "convertTo" should be instance, not a pointer of instance.

First pull request was created for master branch.
But it should be marged for 2.4.
https://github.com/Itseez/opencv/pull/2113

Also deleted miscellaneous remaining multimon cruft.
Deleted #include <winuser.h>, because <windows.h> includes it
already.

This should have a nice side effect of preventing us from
accidentally using any Windows API that's too new.

the `map` buffer does not have the same size with CUDA and index starts at [1, 1] instead of [0, 0].