What i did / Steps to reproduce

Visit this map.
Hanging signs are not rendered correctly. Examples of hanging signs in the world:

• [685,104,1701] (I ran bluemap debug world command - see Context for the output.
• [683,109,1686]
• [685,109,1685]

I suspect that it might be related to #145, but it's a shot in the dark.

Expected result

Hanging signs are rendered correctly

Actual result

Hanging signs are not rendered correctly, and is replaced by the "pink and black" missing texture.

Context

BlueMap Version: bluemap-5-7-paper.jar

[03:18:03 INFO]:   BlueMap   World-Info (debug)   > 
  position: ( x:  685  | y:  104  | z:  1701  ) 
  block:  inecraft:oak_hanging_sign[rotation=8,waterlogged=false,attached=false]
  ├ biome:  inecraft:taiga
  ├ block-light:  10
  └ sky-light:  14 
  chunk: ( x:  42  | z:  106  )
 ├ is generated:  true 
 ├ has lightdata:  true 
 └ inhabited-time:  1303243 
  world:  dominicanas#minecraft:overworld
  ├ name:  dominicanas
  ├ min-y:  -64
  ├ height:  384
  └ spawn: ( x:  0  | y:  67  | z:  0  ) 

dump.json

This bug got already fixed with e1e9212, the fix will be included in next release :)