2.20.0 * Remove trailing spaces. (Miroslav Bajtoš) * Improve instance-level operation hooks (Fabien Franzen) * Fix the test case (Raymond Feng) * fix foreign key dataType bug (didikeke) * Reformat notifyObserversOf context argument (Fabien Franzen) * Implement operation hooks' context (Fabien Franzen) * Allow submodel to hide base properties (Raymond Feng)