Changes from 0.1.2 to 0.1.3:
-added Droid Assembler building and icon for it
-added intermediate droid item which is placeable by player or inserted into Droid Assembler to produce a "deployed" Droid which is spawned nearby.
-Droid Assembler spawns finished deployed droids to the RIGHT HAND SIDE of the building (this is just how it's coded for now. I'll do building-rotation based spawning location later)
-Droids gather into squads of 5 (default, changeable in config.lua) and then hunt for enemies. enemies within 5000 tiles, biter and/or enemy player forces.
-Droids auto-join nearby squads (configurable range config.lua) or create their own new squad if nobody nearby
-Droid's animations and selection box etc were fixed, much better now.
-Recipe adjusted to use basic armour not heavy armour - this has reduced the cost in steel significantly. 
-Reduces Droid's resistances to be more in-line with their downgraded armour. 
