New estimates (data and do files updates; no code updates)

[pbronka]

This issue describes changes that need to be implemented to accommodate updates to the initial populations and estimates introduced in #210

TODO:

• Keep 6-category ethnicity variable in the initial populations and to evolve in the simulation. Move mixed white to white category, so mixed becomes mixed non-white.
• Aggregate up to 4 categories on the fly when required by the regression models
• Children inherit ethnicity from mothers

2. Dhe_pcs and dhe_mcs:

• Merge regression models predicting dhe_pcs and dhe_mcs into the code (from Daniel?)

3. Dlltsd01:

• Drop the dlltsd (i.e. the new dlltsd01 version is now used in the regression models. Substitute the new version, dlltsd01, for the old one, dlltsd, but don't maintain both in the model code).

Originally posted by @pbronka in #210 (comment)

4. Making sure that the modifications to the do files and initial population retain changes introduced by @andrewbaxter439 (e.g. financial distress)