Shock Gloves fix

Two separate changes were required. 1) commenting out the (assumedly
bad) re-declaration of RangedAttack in other_mobs.dm and 2) moving the
line "if(!mutations.len) return" BELOW the power glove line.  This means
people without powers can use the gloves also.

It's tested as working, but I haven't tested to see if it's broken any
other ranged attacks due to what I changed.  You may want to text xeno
projectiles etc and anything else that uses RangedAttack.