Review and possibly update Int columns with new incoming content

[duffn]

New content created by contributors may have values in fields like encumbrance, rarity, damage, etc. that are not Ints. It may be that these do actually need to be strings.

Review and change columns to string types if necessary.

Related to #45.

Examples

• https://docs.google.com/spreadsheets/d/1FgGOmFdgbqTx8l4HVCT0huPdtztDUfzaZB04ur-SB6M/edit#gid=251391118&range=D12

From a contributor

I believe the book uses "-" to differentiate from Incidental items ( which would be "0"). I can switch it to 0, but wanted to run that by you first.

[duffn]

This is being done as I add data for CotR in #88. After I’m done with that first new book, we should have all of the columns updated appropriately.