Set up macro targets for humangenerator

[grebz-dev]

Macro modifiers give defined named ranges. Individual targets in data/targets/macrodetails are named in hyphenated groups of macros, eg, race-sex-age.target or sex-age-muscularity-proportions.target, where the names correspond to macrotargets. Presumably the named ranges in the macro.json definition are the weights for which a macro modifier will switch to targeting a different combination of macrotargets.

Calculating their application would involve:

• Tracking applied macro modifier values
• Determining appropriate target component names based on ranges and macro modifier values
• Switching between macrotargets when appropriate
• Normalizing weights between applied macrotargets