TODO

[jhelvy]

I'm just collecting some todo items here from existing issues:

• Write a function to handle encoding data with an outside good (Function to re-code data with outside good #52).
• Revise encoding to handle effects-coded data (effects coding #46).
• Restrict WTP space scale parameter to only be log-normal or censored-normal to force positivity (see this comment).
• Revise how the number of draws is determined based on the model (see this comment and also this SO post).
• Integrate xlogit as an option for supporting large N draws and speed (Integration with xlogit  #54)