Added support for filtering manual (drag and drop/shift+click) inputs into the Filtering Hopper Gui slots

Sort of a proof of concept for filtered manual inputs. Still not totally sure if you want this or not, but the Filtering Hopper was the perfect thing to implement it on first because the Filtering Hopper code is really basic. This opens the door for filtered manual inputs for Filtering Chests, but that might be a bit more complex.

The only sort of weird thing is that I had to duplicate a lot of code from ContainerFiltered (detectAndSendChanges and all related functions) so that the client would get its filter synced when the hopper Gui was opened.