Addition of (OPTIONAL) input/output chests for factorymod

[Convoy20]

This is a pretty simple addition.

Normal factory: https://i.imgur.com/UBJjqDu.png

The revised change: https://i.imgur.com/BTQn7rL.png

In this setup, the chest connected to the crafting table is considered the input chest, and the chest connected to the furnace is considered the output chest. When a factory runs, it would take items from the input chest, and if an output chest exists, put the finished product in the output chest.

There would have to be priorities for multiple chests connected to the furnace, since it's relatively arbitrary, north, east, south, then west of the furnace on a vertical plane, then bottom, then top.

https://i.imgur.com/vXoEmhN.png

Same thing for crafting table.

Two factories may share input/output chests.

This could be added only for creation of new factories, as not to affect existing factory rooms.

There might be a more elegant way of implementation but this seems ok to me.

[caucow]

For the sake of not forgetting/getting lost in the endless void, a link to a concept mockup video example thing for configuring I/O chests in a way similar to many forge mod factory blocks:

https://youtu.be/X6yY2kb5L9g

For user convenience/familiarity/[matching the modded "standard"] the directions would be relative to the front of the furnace (ie if the user is standing in front of the furnace, looking at it). The "Back" side chest is shown in the bottom right square of each 3x3 I/O config panel, and if added, the "Front" side chest could be shown in the top right (I didn't have a front "button" in the example video).

[caucow]

IO config has been merged, issue can be closed