Industrial: Toggleable on/off splitters and combiners.

[Besieged]

Create splitters and combiners that are able to be toggled on and off.  Allowing for more dynamic industrial setups with less conveyors.  Being able to switch on/off feeder or destination splitters/combiners allowing one conveyor group to handle all the input or output that would have taken multiple conveyor groups.

[RedBarrelBaron]

Hear hear!