* Some UI implementations

* Added opencv wrapper

* Updated Opencv wrapper

* Moved initialization stub

* Added threshold

* Setup interaction with canvas

* Fixed couple of issues

* Added threshold, changing size via ctrl

* tmp

* Aborted host change

* Fixed threshold

* Aborted host

* Some fixes

* Using ready label selector

* Raw implementation

* Added additional arguments

* Fixed some minor issues

* Removed unused file

* Fixed tool reset

* Added short instructions to update opencv.js

* Fixed corner case

* Added error handler, opencv version, updated cvat_proxy & mod_wsgi

* OpenCV returned back

* Using dinamic function instead of script

* Updated changelog & version