Use ROI selector in python samples

added error msg for samples

Sample has been renamed: tld_test.cpp->tracker_dataset.cpp
Updated to read parameters from cmd:
-Algorithm name
-Root dataset path
-Dataset ID
-Number of targets to track

Sample has been renamed: tld_test.cpp->tracker_dataset.cpp
Updated to read parameters from cmd:
-Algorithm name
-Root dataset path
-Dataset ID
-Number of targets to track

1. Multi-tracker classes (multiTracker.cpp)
2. Multi-tracker example (multiTracker_test.cpp)
3. Fixed a rare bug (OpenCL runtime error)

1. Multi-tracker classes (multiTracker.cpp)
2. Multi-tracker example (multiTracker_test.cpp)
3. Fixed a rare bug (OpenCL runtime error)

Sample has been renamed: tld_test.cpp->tracker_dataset.cpp
Updated to read parameters from cmd:
-Algorithm name
-Root dataset path
-Dataset ID

Sample has been renamed: tld_test.cpp->tracker_dataset.cpp
Updated to read parameters from cmd:
-Algorithm name
-Root dataset path
-Dataset ID

1. Added 2-nd level of parallelization of NN on OpenCL
2. Restructured detector - now all filters work independently:
Variance Filter->Ensemble->NN,  through "buffers"

1. Added 2-nd level of parallelization of NN on OpenCL
2. Restructured detector - now all filters work independently:
Variance Filter->Ensemble->NN,  through "buffers"