Integrate nuanced demographic info into shelter calc

[tieganh]

HAZUS methodology, Section 14.3, describes shelter needs calculation. Murray had wanted to include some more nuanced indicators (Imm_LT5, Live_Alone, No_EngFr, LonePar3Kids, Indigenous - see attached below), but we don't have data on how those indicators affect demand for shelters. As of Sep 2021 we're omitting these indicators because we don't have that data.

displacement-shelter-models-with-damage-factors.pdf

We're also changing Murray's 'demographic' section back to 'ethnicity' as it was in HAZUS, using the 'VisMin' indicator, because groups of indicators must be correlated. In other words, the percentage of the population must sum to ~1 over the category. In future this could be adjusted to include more groupings than just 'VisMin'.

Assigning @yipjackie but if someone else has capacity and wants to work on this then they're welcome to. Some cool work has been coming out of UBC that could be relevant for Canadian context of displacement. Also no pressure for Jackie to implement, as even HAZUS folks decided not to implement anything besides ethnicity and income.

Relevant files are building DSRA and SAUID. Can contact @wkhchow for more info on these.