Passing the object is no longer necessary

[ChrisRackauckas]

There are a lot of references to passing a call-overloaded immutable for performance. In Julia v0.5 and onwards, each function is a separate type (essentially a call-overloaded immutable), so this specialization on the type happens automatically. It shouldn't be necessary anymore, and there shouldn't be a performance difference anymore. You may just want to drop the old timing, keep the type-version timings, and drop references to this.