fetch partially loaded taxa more safely
fetch partially loaded taxa more safely

stashing an RKObjectLoader property should avoid a use-after-free crash
in the event that the request doesn't succeed or can't be loaded. not
sure why RKObjectManager isn't retaining the loader in that situation.

inaturalist/INaturalistIOS,inaturalist/INaturalistIOS,inaturalist/INaturalistIOS,inaturalist/INaturalistIOS