I downloaded one Photos Extension: BeFunky Express. Unfortunately it seems that what it does is exactly what Plug-ins for Aperture used to: generates a jpg file out of the RAW. Also it does not allow you to go back and re-edit what you have done with that extension. You can revert to original (which simply gets rid of the jpg and shows the raw again). Disappointed to say the least.
I am not sure if the MacPhun tools/extension would work the same way. Anyone to comment on?