Reduce fuel consumption rate

[Aeneas137]

Fix the fuel consumption problem--way too fast.
Also, in the original game the ship ONLY uses fuel in hyperspace so let's make sure fuel isn't used in-system. The player shouldn't be so easily frustrated by running out of fuel.
Also, should we just remove fuel usage when landing on planets? It sort of discourages the player from exploring if fuel cost is too high. Or just reduce it quite a bit?