fixing bug #3345
fixing bug #3345. don't use BORDER_ISOLATED alone. it should be combined with some border type
Viz initial backport, compilation fixes, moved viz/viz.hpp header according to 2.4 style
fixed documentation warnings
added guard to prevent linking VTK with Qt5
temporary disabling hanging test
Improvements in package build.
Merge pull request #2197 from asmorkalov:ocv_packaging2
Merge pull request #2194 from apavlenko:2.4_perf_haar_iter
VTK off by default
OpenCV C/C++/OCL/CUDA samples install path fixed. Install rools for tests added.
Code review notes fixed.

Env setup for testing package implemented using /etc/profile.d;
Variable with path for all native samples added;
Path for test binaries and test data updated.
Merge pull request #2209 from asmorkalov:ocv_test_install
Merge branch '2.4' into blur_border_isolated
fixing bug #3345. use norm to make sure two matrices are the same.
fix #3477:

CV_CAP_PROP_SUPPORTED_PREVIEW_SIZES_STRING property is not supported
by all VideoCapture backends. Some backends can return 0.0 or -1.0.
Merge pull request #2097 from pclove1:blur_border_isolated
Merge pull request #2205 from jet47:bug-3477-fix
Multiple fixes for tests deb package build.

Added opencv_testing.sh.in file;
opencv_testing.sh installation guarded by OS check.
Merge pull request #2215 from asmorkalov:ocv_testpack_fix