Bug fixes

Fixed island level calculations. Some islands were missing chunks. It depended on the coords of the island.
Fixed biome setting alignment to match island block boundaires instead of chunk boundaries.
Stopped checkmove occuring unless a player moves in x or z - should improve performance.
Adds saving of the island grid at key points, like island deletion, changing of ownership, new island, etc. Also adds a 5 minute repeating save to capture island setting changes. This should help protect from issues after a server crash.
Challenge completion broadcast messages are now in the language of the recipient not the completing player.
Acid drinking death message is not sent if mute death messages is true. Message is also displayed in local language of player.
Check for over-long panel titles - was enabling item removal in some locales.