In 1.6.4, addTradesFarmer doesn't do anything, so I'm not sure if I should try to figure out what it was intended to do and implement it or to just remove the config option from the 1.7.10 version.

Here's the config comment for some context:
Add HarvestCraft crop produce to the items farmer villagers will buy (HarvestCraft)

We should verify that it isn't something in HarvestCraft for 1.7.10. If it isn't, then I guess it's our choice. Personally, if we have the config option, and the classes already, I say we do it,