(svn r14672) -Fix [FS#2444]: Property 7 and callback 12 were broken for aircraft.
Now callback 12 is properly called also for 'mail'.
If the callback is not used, 'mail' uses 1/4 of property 7 (rounded up).

bin/lang/*
bin/opentd*
bundle/*
config.cache.*
config.log
config.pwd
Makefile
Makefile.am
media/openttd.desktop*
objs/*
src/rev.cpp