EitB Dev Journal 2: Eras

Fall From Heaven was originally split into three eras: Ancient, Classical, and Medieval.  Eras are used to set the starting techs for non-ancient starts and also delineate the technology tree into distinct sections. These eras, however, are too broad.  

EitB then, will have 5 eras, tentatively named:

1. Thaw (Worker Techs including Bronze Working and Archery)
2. Discovery (All techs that enable T2 units and Smelting)
3. Expansion (All between T2 and T3)
4. Innovation (All techs that enable T3 units and Arcane Lore)
5. Mastery (Everything else)

Start Era Options; System Use Eras are used for state religions.

I plan to use these new eras to modify the coloring on the tech tree to make a visible distinction between the technology tiers, building on the Heat Map mod I did last year (that colored techs in the tree based on their cost to research).