Resolve "Sort example by topics and remove numbering"

What does this MR do?

Remove numbering of Samples, and add topics folders.

• AR:

  • ExFrameByFrame
  • ExRGBDManualAR
  • ExSimpleARCVOgre
  • ExVideoFiltering
  • ExIgtl
  • ExRGBDStream
  • ExSolvePnP
  • ExVideoRecorder
  • ExOgreRGBDStream
  • ExSimpleARCV
  • ExStereoARCV
  • ExVideoTracking

• Core:

  • ExActivities
  • ExDump
  • ExTimeLine

• ImageProcessing:

• ExDicomSegmentation

• ExImageMix

• ExImageSubstraction

• ExRegistration

• UI:

  • ExWheelWidget

• Visu:

  • ExSParameters
  • ExVolumeRendering

How to test it?

Compile all the samples and Run it, it should work as before. (some of them already have some issues).

Additional tests to run

• Build & Run on Windows
• Build & Run on Linux
• Build & Run on macos