Fix debug build broken issue.

Fix the following error:
/usr/bin/ld: ../../lib/libopencv_ts.a(ts_gtest.cpp.o): relocation
R_X86_64_32 against `.rodata' can not be used when making a shared object;
recompile with -fPIC
../../lib/libopencv_ts.a: could not read symbols: Bad value
collect2: error: ld returned 1 exit status
make[2]: *** [lib/cv2.so] Error 1
make[1]: *** [modules/python2/CMakeFiles/opencv_python2.dir/all] Error 2
make: *** [all] Error 2

datasets module: enhancements

latentsvm caskade

reworked PR 3

comment off #include "opencv2/core/private.hpp". It prevent the project from being referenced from outside the opencv library.

renaming + docs;

comment off #include "opencv2/core/private.hpp". 

comment off #include "opencv2/core/private.hpp". It prevent the project from being referenced from outside the opencv library.

adas fix

Adaptive manifold filter improvements

adding more clear documentation

Adjusted test cases for SURF_CUDA, using new APIs

datasets module: enhancements

Fixed some existing doxygen warnings

Java wrappers for bioinspired module

Bugfix: NNs not found due to precision error.

quickly corrected the previous refactoring of features2d/xfeatures2d

quickly corrected the previous refactoring of features2d/xfeatures2d: moved from set(SOME_PROP, val) to setSomeProp(val)

Refactored features2d & xfeatures2d