switch to opencv

[axet]

Hello!

Here a few exaimples how to use OpenCV to scan / transform and prepare scanned docuemnts. Results are much better then current scantailor release.

Would be nice to have opencv as part of this project.

https://pyimagesearch.com/2014/09/01/build-kick-ass-mobile-document-scanner-just-5-minutes/

[axet]

Also I found this one:

• https://mzucker.github.io/2016/08/15/page-dewarping.html
• https://github.com/lmmx/page-dewarp