Towns and Nations 0.15.4

New :

• Add balance check when selecting "create a fort" button.
• Add minimum distance between 2 towns to disable settling too close to another existing town TerritoryClaimBufferZone
• Added 2 new events to newsletter : Landmark claimed & Landmark lost

Bug fixes :

• Fix minimum version check for SphereLib not being set to 0.5.2
• Fix message PLAYER_NOT_LEADER_OF_REGION to PLAYER_NO_PERMISSION when player does not have permission to claim region chunk only. Remanent from before the introduction of roles in regions.
• Fix RegionAllowNonAdjacentChunks not being used
• Fix missing lang : GUI_SETTINGS_CHANGE_TERRITORY_NAME
• Fix missing placeholders on landmark rewards in admin menu

Others :

• Centralised code for towns and region claiming
• All messages localised (better Lang#get)