0.5.12

Change set since 0.5.11:

198fe6d: Bump to 0.5.12
2fcf54d: Actually delete area data when unclaimed
37ac232: Also include dimension in the area detail
cfb8c15: Experimental: area.allow_fire_spread
6ecb964: Give a message when right-click block is disabled in an area
1bde501: Limit Y range for rendering
3a682a1: /ac mine
c03bb18: Experimental: auto-completion support for /ac current properties set/unset
4c91953: Drop the usage of dynamic context
a88cb15: Welcome message is now translated and controlled by permission
d3b46ef: Experimental: welcome message on first time when player enters an area
2405e92: Attempt to fix the serialization in TomlBasedAreaRepository