[ok] Early cargo planes

[KestrelAIH]

Could the rate at which early types (eg dc3/commando/Viking) get auto-converted to cargo planes be reduced? The situation often arises that available planes rapidly get auto converted to cargo (but no demand for them) leaving no pax versions (but with demand for them! Could it not be a bit more like later in the game where you buy a second hand plane and convert it yourself? Or at the very least slow down the algorithm or whatever it is so that expanding airlines still can grab passenger versions?

[Sami]

It doesn't convert anything to the first 5 years (was previously 4 years). Also decreased a bit the number of conversions per each time. It also doesn't convert any planes that are younger than 15 yo (no changes to this).