dualswords out of energy cutlass fix, take 2

New path for energy swords, /obj/item/weapon/melee/energy/sword/saber and the different type of colours (purple, red, green, blue) are childrens of it.
You can only use sabers to create a dualsword and to archieve the funky colours with the multitool.
Dualswords now will be eqipped on hand once created instead of staying on the floor.
Fixes issue #4050
See previous complain on PR: making a already unpicked cyborg module's only reason to get picked(emagging) extra useless is bad, because a module that costs 500 per 30 damage hit is bad. Compare to the cyborg laser, which costs 100 per 20 damage shot and is ranged and on the secborg.