Revert "add compatibility modules for Props -> Properties rename"

This reverts commit 1c06ece58e0940a24dbb50a3c8c7811dbe08b8a5.
Renamed releases/release-notes.txt -> CHANGELOG
Renamed releases -> notes
[ CHANGELOG ] Removed compatibility modules for Props -> Properties rename
[ releases notes ] Minor change
[ release ] Preparation for releasing version 0.9
Removed release-specific information
Merge branch '2.4.2.1'