Add other foundation types

[abpoll]

Currently only have slab, crawl space, and basement. In other counties, I've seen I/P/W. Looking at https://www.fema.gov/sites/default/files/documents/fema_hazus-6-inventory-technical-manual.pdf (Table 5-11) and https://github.com/HenryGeorgist/go-fathom/blob/master/compute/foundationheights.go, should be able to use the same values for I/P/W. The NSI technical documentation indicates (C = Crawl, B = Basement, S = Slab, P = Pier, I = Pile, F = Fill, W = Solid Wall). Should anticipate Fill as well. According to Table 5-11, looks the same as slab.
F: [0, .5, 1.5]
I: [6, 9, 12]
P: [6, 9, 12]
W: [6, 9, 12]