-This means that one company can only have one setting for renew and replacing
more clients will not fight due to different settings anymore
-This is a needed step in the line to fix autoreplacing dualheaded locomotives
NOTE: savegame revision bump (peter1138 + me in coop)
Renamed railtypes.c into railtypes.h, all other tables are in .h files. (It should be in the tables dir but I couldn't figure out how to get it there without deleting it first).
Added const and extern.