[Fixed] selling an item from stockroom no longer counts that item's size
twice in the item count check
[Fixed] retrieving an item from a vendor now considers the item's size
when checking inventory space
[Fixed] relisting a sale from stockroom to always place the sale back
onto the vendor it was already on - mantis 4171, 3616
[Fixed] a player can no longer place items for sale on vendors if they
have more vendors than their maximum

Change-Id: I175a67e8d5cb408c907755e5daf6ce2cab698d63