utility icon for all technologies.
Categories: economy, garrison, army.
worker-rations: lvl1, lvl2, lvl3.
Food is good: lvl1, lvl2, lvl3.
Free housing, Give 'em fish, teach 'em fishing.
Sickles, calendar, crop rotation.
Saws, bow saw, mechanized saw.
mining picks, prisoner driven wagons, mule driven wagons.
stronger walls: lvl1, lvl2, lvl3.
hidden storage, extra storage, super storage.
Ugly statues: lvl1, lvl2, lvl3.
training swords, light swords, sharp swords.
Trowing spears: lvl1, lvl2, lvl3.
Shield doctors: lvl1, lvl2, lvl3.
light armor, bronze armor, iron plate armor.
Precision training: lvl1, lvl2, lvl3.
horse shoes: lvl1, lvl2, lvl3.
stone saw, rudimentary wheel, pulley.
