arogue5: make alchemy jugs survive a save and restore. Alchemy jugs are refilled by the alchemy() fuse, which takes a pointer to the jug object as an argument. When written to a save file and read back out, the pointer is unlikely to point anywhere useful. Instead, rs_write_daemons() now stores an index into the player's pack or the list of objects on the floor. rs_read_daemons() uses this number to locate the object when restoring. This change should not cause any new issues with old savefiles, but it is unable to make a broken alchemy jug work again.