* Add learning-based super-resolution module

Adds the module plus loading classes for SR data

Complete with docs, tutorials and tests.

* Fix typo

* Small commit to restart buildbot

* Change refs from arXiv to official

* Remove video string

* dnn_superres: update perf test code

* dnn_superres: test fixup

* Adding dnn based super resolution module.

* Fixed whitespace error in unit test

* Fixed errors with time measuring functions.

* Updated unit tests in dnn superres

* Deleted unnecessary indents in dnn superres

* Refactored includes in dnn superres

* Moved video upsampling functions to sample code in dnn superres.

* Replaced couts with CV_Error in dnn superres

* Moved benchmarking functionality to sample codes in dnn superres.

* Added performance test to dnn superres

* Resolve buildbot errors

* update dnn_superres

- avoid highgui dependency
- cleanup public API
- use InputArray/OutputArray
- test: avoid legacy test API

* Add pattern generator tool

* Fix help error

* Update readme

83fc27cb

* Fix bug: Invalid Syntax at line 14(draw_motion_comp method)

* Fix bug: TypeError- integer argument expected, got float

* Fix bug: clean up the camera by adding .release()

* removed private flann documentation
* common tutorial images moved to doc/images
* grouping issues

original commit: https://github.com/opencv/opencv/commit/f3aab47f94f1dc5466ade4e98194f7ab9a02133a

Moved aruco dictionary globals into getPredefinedDictionary so constructed on first use, to allow lazy-loading of the opencv DLL

tesseract 4.x headers require C++11 (can't be used by OpenCV 3.4 without C++11)

  * add -Wno-psabi when using GCC 6
  * add -Wundef for CUDA 10
  * add -Wdeprecated-declarations when using GCC 7
  * add -Wstrict-aliasing and -Wtautological-compare for GCC 7
  * replace cudaThreadSynchronize with cudaDeviceSynchronize

original commit: https://github.com/opencv/opencv/commit/40c71a2463f27ec8625cba4823fcb82f8bb77590