fix for fuel issue

Ship.Refuel = function (self,amount)
    local currentFuel = self.fuel
    local removed
    if currentFuel == 100 then
        Comms.Message(l.FUEL_TANK_FULL) -- XXX don't translate in libs
        return 0
    end
    local fuelTankMass = ShipDef[self.shipId].fuelTankMass
    local needed = math.clamp(math.ceil(fuelTankMass - self.fuelMassLeft), 0, amount)
    if FuelHydrogen == true then
        removed = self:RemoveEquip(Equipment.cargo.hydrogen, needed)
    else
        removed = self:RemoveEquip(Equipment.cargo.water, needed)
    end
    self:SetFuelPercent(math.clamp(self.fuel + removed * 100 / fuelTankMass, 0, 100))
    return removed
end