updates documentation for the text module

Adds OCRTesseract class and sample demo

Adds The exhaustive search algorithm and updates the previous groupining algorithm; Add xml files with default classifier models;

added "text" module; added linemod to rgbd module, fixed compile errors in rgbd

Split highgui module to videoio and highgui

Tracking-Learning-Detection and MedianFlow

Fix include of imgcodecs

fix compiling reg module after separating imgcodecs from highgui