This contribution changes the way how trackers should be implemented by
programmer. It should be noted first, that from the user prospective,
Tracker::create() method still can be called with the same effect.
However, there's no more thing as a "constructor" for Tracker, they
should be created via static functions, e.g.
    static Ptr<TrackerMIL> createTracker(const TrackerMIL::Params &parameters=TrackerMIL::Params());

From the programmer's perspective now for every tracker what is declared
in tracker.hpp header is more a "interface", while the real
implementation class can (and has to) be implemented in .cpp file.

Changes in documentation are also included.

(fix docs warnings)

Change Rect to Rect2d in Tracker::update() and ::init()

I've changed Rect to Rect2d in Tracker::update(), Tracker::init() and
all related methods (including documentation). This allows to initialize
trackers with double-valued rectangles, thus adding versality. Besides,
trackers also can output double-valued rectangles, which may be
beneficial in some scenarios.

However, it remains to change UML diagrams in documentation to tracker
module, as they still display methods above with old signatures.

Enable travis and other fixes

New feature to tracking sample

Now initial bounding frame can be given in command-line, as an alternative
to manual selection via mouse. Bounding frame is given as optional last
argument in the format "x1,y1,x2,y2" where x's and y's are integers,
symbolizing bounding box with opposite vertices (x1,y1) and (x2,y2).

This reverts commit 2fb9cac0.

added a local extremum blob detector 

added a local extremum blob detector that can be used after retina module to detect transient areas (low level saliency)

just added procedure if using cmake-gui interface

add an RGBD module

reg module: Add sample and README file

README.md file with a short description of the module is added. An
example on how to use the module can be found now in reg/samples/.

added perf tests for bioinspired

bioinspired -> opencv_contrib

The implementation of particle filtering tracker

This contribution aims to implement the sampler based on particle
filtering within a generic tracking API that opencv has. Maybe, one day
it will become a part of a robust solver.

The implementation of particle filtering tracker

This contribution aims to implement the sampler based on particle
filtering within a generic tracking API that opencv has. It still
remains to write the documentation.

Added perf_test and test based on distance and overlap for tracking API

Added OPE tests tracking

- Reinitialized random number generator (TrackerMIL and TrackerBoosting)
- Removed unused meanSigmaPair

Changed sample tracker.cpp with a list of images instead the video file

Modified OPE tests tracking

- The overlap threshold varies from 0.0 to 1.0
- The location error threshold varies from 0 to 50

Changed name for the tests

Removed unused field

Enlarged first rect of 10% respect the ground truth

Added TRE test

TRE test for the temporal robustness evaluation

Added SRE Test (spatial robustness evaluation)

- Removed the enlargment of the first frame
- TRE corrected the computation of the distance and the overlap
- TrackerBoosting changed the search factor

Fixed last segment in test TRE

First stub for regression test

Added test for faceocc2

Added perf_test for mil and boosting trackers

Modified SANITY_CHECK with ERROR_RELATIVE

In xml generated added the ratio between of the correct bounding box (based on dynamic threshold)

OPE Test: works with video and not with sequence of images

TRE Test: works with video and not with sequence of images

SRE Test: works with video and not with sequence of images

Perf test: works with video and not with sequence of images

Removed unused file

sample tracker.cpp: works with video and not with sequence of images