updated gitignore to ignore docs
updated gitignore to ignore docs

victoraliss0n/geofire-objc,ObjSal/geofire-objc,firebase/geofire-objc,firebase/geofire-objc,victoraliss0n/geofire-objc,ObjSal/geofire-objc,ObjSal/geofire-objc,victoraliss0n/geofire-objc,firebase/geofire-objc,firebase/geofire-objc