Custom User Data

@esoergel @twymer
whenever we introduce brand new models (and dependent couch views) i think we should always consider the tradeoffs between putting those models in a new database versus using the existing ones. the benefit of a new database is (1) they don't contribute to indices of other documents and (2) the database will be small so any future changes to views will reindex fast. the downside is that you can't create databases via APIs in cloudant (at least to my knowledge) so there's a manual step required per server of making the database and giving it the right permissions.

a reasonable compromise might be to spin up a new database for "non-essential" stuff, and use it for new models (although this obviously has similar problems to the single database option if it gets too big). curious if @dimagi/team-commcare-hq has opinions on this and maybe specifically @dannyroberts