Verify and extend star canonicalisation

[CyberiaResurrection]

Now the basic star canonicalisation guts is in, extend them to (mostly) handle the T5 trade classes. The major exception is Barren/Dieback trade codes - I decided to send up what I had to stop the perfect being the enemy of the good.

In T5, both Barren and Dieback require Pop 0, Gov 0 and Law 0 - Dieback also requires Atmo 2+. As currently, Pyroute treats Barren as requiring only Pop 0, I've left that as-is for the moment.

This required:
Extending the default size option in _{check,fix}_planet_code to handle size E and F planets.
Likewise extending the default size option in _{check,fix}_trade_code to handle size E and F planets.
Extend Hi pop checks to handle population codes of E and F.
Extend _{check,fix}_planet_code calls for the "Oc" trade code to handle size E and F planets.