-Fix: When inserting an order for a ship while checking the distance between the new order and the order it is inserted after adhere the order types to determine the correct type of destination (i.e. station or depot)
Also do a better job in determining the preceding order
NOTE: 0.5 candidate
This means that "v->type" can be used as array indexes instead of VehTypeToIndex() (or "v->type - VEH_Train/0x10 as the code still used in some places)
Surprisingly this can be done without changing the savegame format