Playtest build 0.20

-Fix bug - unable to start new game properly
-Fix bug - restock amount display wrongly
-Fix bug - put box on warehouse shelf but unable to take it out until restart
-Fix bug - warehouse shelf tag should not be able to set price
-Fix bug - right click warehouse shelf while holding opened box will bug out
-Fix bug - right click while holding item will make warehouse shelf price tag gone
-Fix bug - when holding item and look at box, highlight won't turn off when look at another box