Add aircraft hours and maintenance history

[sushiat]

• Airframe and engine hours
• Update hours from completed/aborted flights (return to destination)
• Create history of maintenance performed for each aircraft, also determines when next check etc. is due
• Apply random history to generated aircraft population? Or is this just wasting db space/performance?
• Auto generated aircraft should pick random values for times from ~10% to 80% of usable before check

[sushiat]

This ticket will be parked for a bit until the Alpha5 revive of existing elements is complete