[svn, lua] frozen shards

[nukularpower]

This sling ammo (frozen shards, using Hare-skin sling, if that counts) causes a cloud AoE effect. Every turn, this AoE generates a lua error. It seems to be related to the frozen effect.

Also, in case it counts, this was in Dreadfell. Havent tried outside yet.

Lua Error: /engine/Map.lua attempt to index global 'overlay' (a nil value)
At [C]:-1 __index
At /engine/Map.lua:1003 processEffects
At /mod/class/Game.lua:1090 onTurn
At /engine/GameEnergyBased.lua:88 tick
At /engine/GameTurnBased.lua:46 tick
At /mod/class/Game.lua:1015
---------------- Stack Dump ----------------
2: table // b75e98
1: table // b75e98
--------------- Stack Dump Finished ---------------
[LOG] Bilbo hits orc grand master assassin for #1133F3#21 cold#LAST# damage.
[LOG] Bilbo hits elder vampire for #1133F3#6 cold#LAST# damage.

[darkgod]

fixed