Tracker - basic DB schema

If interested, this is the rough schema for the tracker program. Essentially a Ship object is the primary thing - you can run multiple ships in different Traveller versions.  Ships have a ship class that determines the basic things like tonnage, jump and maneuver, cargo and passenger capacity.  A ship is on a world that has all the stuff from the TravellerMap API (I store everything in the SQLite DB - you set a ship sector and if it is not already in the system, I go out & get the info and store it locally. The idea is that this can still be useful even if not connected to the internet). A ship also has cargo (which is speculative cargo as well as bulk cargo, and passengers are basically treated as cargo but take no cargo space).

A few other support tables, and a few things still in flux.  Not all the tables are listed.

There is also a seed class that preloads a few classes, the Classic Traveller cargos and a few other things the first time you run the program.