* Try to resolve image paths by replacing backslashes.
* Some changes suggested by CI
* Removed usage of <filesystem>.
* Removing usage of C++20/C++23 features
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Co-authored-by: Kim Kulling <kimkulling@users.noreply.github.com>
Changed copyright end year to 2020 in every reference "Copyright (c) 2006-XXXX, assimp team".
Changed copyright end year to 2020 in every reference "Copyright (c) 2006-XXXX, ASSIMP Development Team".
Changed copyright end year to 2020 in LICENCE.rtf.
Changed copyright end year in CMakeFiles.txt files and any other places referencing Assimp with a copyright start and end year.
