Method release

API/fleece/slice.hh:422–422

        // Manual ref-count management. Use with extreme caution! You probably don't need this.
        alloc_slice& retain() noexcept                      {_FLBuf_Retain(buf); return *this;}
        inline void release() noexcept                      {_FLBuf_Release(buf);}
        static void retain(slice s) noexcept                {((alloc_slice*)&s)->retain();}
        static void release(slice s) noexcept               {((alloc_slice*)&s)->release();}