Adds a manual crank cell charger

Created by: JustSumBody

Revival of #4947 Constructable from an APC frame, metal rod, cables, and wirecutters Insert a power cell and attack_self it to crank it for a whopping TEN WATTS JOULES per crank

Video: https://dl.dropboxusercontent.com/s/md3dytttf6o2iu6/2017-01-21_07-10-31.mp4

NOTE THAT FOR SOME REASON CRAFTING ONE MAKES TWO THIS IS NOT INTENDED AND I'M NOT SURE HOW TO FIX No longer makes the result twice, but it throws the same debug warning that wall mounted holomaps throw when you finish the last step: ADMIN LOG: Holy shit /datum/construction/reversible/crank_charger/(/datum/construction/reversible/crank_charger) is trying to set its new index to 0! how the fuck did this happen? I don't know, our direction is forward old index was 1. User is justsumguy, itemused the screwdriver, step /list I'm not sure if what's going on is a result of construction datum code itself or my/Deity's use of it. @ComicIronic

Besides that, I guess it could do with construction sprites or an inhand but eh.