AuctionHousePlugin

Changelog:

• fixed a typo in "ban-usage": It's supposed to be a § sign and not a $ sign.
• added PlaceholderAPI support (%auctionhouse_announcements% > "enabled" or "disabled" and %auctionhouse_active_auctions% > number of active auctions for the player)
• huge performance improvement by keeping the items that are on the ah in memory instead of deserializing them every time again
• made the item displays customizable (the tuff block, the signs and the glass)
• you can now put the currency symbol before the number in item displays
• the config.yml file now generates with comments, but only if the file doesn't exist yet
• added bundles view. Players can now look into bundles just like they can look into into shulkers
• fixed console showing an error message when reloading about the log file
• item displays are now only breakable when having the permission, being in creative mode and sneaking. A break-instruction message appears if you try to break the display while having the permission.