fix shield-slot icon display (change from orders item to shield item)
re-enable player-owned trader npc type
much work on trade order gui, add route-point set and manipulation code.
route-following and refil/deposit not yet implemented
prep/base work on player-owned trader NPC gui and interaction
add implementation of player-owned trader.  It -works-, but needs the
rest of routing and auto-restock finished.
remove some debug output