Bahtinov analyzer for manual focus

[Stanley Dimant]

Using a Bahtinov mask an analyzer of the alignment of the spikes could prove very useful. Should be in connection with a ROI marked on the image with a box so it doesn't try to solve all stars but only one major one inside the ROI. Implementation in imaging, possibly a tab like the imaging preview control window but with extra controls (mark ROI, stretch by default, display of error).

[Stanley Dimant]

https://sourceforge.net/projects/opencvnet/

http://www.emgu.com/wiki/index.php/Tutorial

https://docs.opencv.org/2.4/doc/tutorials/imgproc/imgtrans/hough_lines/hough_lines.html

Hough lines seem to be exactly what is necessary for line detection.

[Stefan B]

Done some basic implementation for it. A new button can toggle the bahtinov aid on and off. The aid renders a rectangle that can be dragged to the region of interest.

Once the feature is robust enough it will find its way into the main branch.

[Stefan B]

First version included in v1.5.0.0 and above.