2.15.0 * Fix id type issue for update (Raymond Feng) * Rename hook "query" to "access" (Miroslav Bajtoš) * Implement intent hook `before delete` (Miroslav Bajtoš) * Remove redundant `.toObject()` call from `upsert` (Miroslav Bajtoš) * Fix regression in `.save()` from 1fd6eff1 (Miroslav Bajtoš) * Fix hasOne remoting (Raymond Feng) * Make sure batch create calls back with correct data (Raymond Feng) * Intent-based hooks for persistence (Miroslav Bajtoš) * ModelBaseClass: implement async observe/notify (Miroslav Bajtoš) * Upgrade `should` to the latest 1.x version (Miroslav Bajtoš) * Fixed nullCheck in validations to correct behavior when dealing with undefined attributes (James Billingham) * Supply target to applyProperties function (Fabien Franzen) * fix id property for composite ids (Clark Wang) * fix id properties should sort by its index (Clark Wang) * Fixed typos and logic for protected properties (Christian Enevoldsen) * adds support for protected properties. (Christian Enevoldsen) * support embeds data for belongsTo relation Signed-off-by: Clark Wang <clark.wangs@gmail.com> (Clark Wang)