Constructable conveyor belts can now be ordered from cargo.
Fixes conveyor switches not having fingerprints. Simplifying the conveyor switch code a bit.
derp
Merge remote-tracking branch 'phil235/ConveyorSwitchPrintsFix' into spacefactory13

Conflicts:
	code/modules/recycling/conveyor2.dm
Constructable conveyors: Corner belts, fingerprint fixes
Removes obsolete attack_hand() from oneway conveyor belt switch
Merge pull request #5581 from tkdrg/spacefactory13

Constructable conveyor belts!