Repaths switchblades under kitchen knifes (shiptest-ss13#3093)

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Repaths the switchblade under the kitchen knife so it isnt snowflaked
and has all the intended knife behavior

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Consistency and the switchblade is able to properly butcher.

:cl:
code: Switchblades are now pathed under obj/kitchen/knife
imageadd: Switchblade sprites moved from items and weapons.dmi to
knife.dmi
/:cl:

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