* Allow extensions to store EffectMetadata.
* Rework gdjs.PixiFiltersTools to allow new effects to be dynamically registered.
* Update EffectsList to read effects from extensions.
* Update GDJS ExporterHelper to export include files for effects
* Rename effectName to effectType to avoid confusions in gd::Effect
* Rename onOwnerRemovedFromScene to onDestroy (because it can be now called when a scene is destroyed)
* Fix it being not called when a scene is destroyed (so behavior don't get a chance to clean up what they have created)
* Fix onCreated being called before the object is fully initialized (for custom behaviors or behaviors relying on an object type)
* Upgrade to Flow 0.92 and make fixes for it
* Convert all extensions to use _("...") instead of t("...") for translations,
to be able to be parsed by gettext
* Handle translation in JS extensions
* Move Providers out of MainFrame
* Remove i18next
* Adapt ExtractTranslations script to handle js files (for extensions)
Florian Rival