small inconsistencies in VesselData members

yikes the issue ran away before I finished typing...

Various of the VesselData members store values represented in seconds. Unfortunately they use various data formats:

• TAp (long)
• TPe (long)
• period (long)
• MissionTime (UInt32)
• deltaTime (float) - I understand the need for this one to be different
• MNTime (UInt32)

While it's not a big deal it makes writing a function that converts seconds to a readable time format (array-of-char) a bit more cumbersome. Maybe you could change that in a future version.

[zitron-git]

OK will fix.