Provide extra fuel

[rogers492]

• [x] About an hour more fuel
• [x] Provided when supply depots are captured
• [x] Vary amount by size of depot

[rogers492]

Depot 55: 00 - Airstrip Depot 54: 15 - Ford Depot 53: 15 - Farm Depot 52: 20 - Quarry Depot 51: 10 - Factory

[rogers492]

Easier way to get the same effect is to add 5 to each groups initial fuel, so 20>>25, 30>>35 etc up to 60>>65. So I will do that instead.

[rogers492]

Done in #64