CHANGE: Reduce the number of alternative destinations for visiting passengers to below the level for commuting passengers.
ADD: Douglas DC2 Pax
CHANGE: Ford Trimotor Pax, retire date.

Signed-off-by: Milko <Beppe@giuseppe.(none)>
ADD: Simuconf.tab settings for the new random number generator settings.
Merge branch 'Payload' of https://github.com/Milkogit/simutrans-pak128.britain.git into half-heights
CHANGE: Alter retirement date for the Ford Trimotor to match with the introduction date of the Douglas DC-2