Handwriting recognition app

[Kevin Kofler]

There are already a few handwriting recognition libraries available, e.g.:

• this really old one (GPLv2): https://github.com/risujin/cellwriter
  
• this one released under the GPLv3 by a commercial company: https://github.com/phatware/WritePad-Han...ion-Engine
  
• this AI (TensorFlow neural networks) approach (MIT license): https://github.com/githubharald/SimpleHTR used, e.g., in: https://github.com/PellelNitram/xournalpp_htr