Don't enable caching until reviewing where it is used

[omnilord]

json.cache! is not currently set to expire in several files. Ensure that caching expires if caching is enabled.

See:
https://github.com/hurricane-response/florence-api/blob/master/app/views/api/v1/shelters/index.json.jbuilder
https://github.com/hurricane-response/florence-api/blob/master/app/views/api/v1/shelters/outdated.json.jbuilder

Other files may be using this as well.

[nihonjinrxs]

@omnilord can you take this one on? I feel like we should clean this up sooner rather than later.

[omnilord]

@miklb Do we have usage statistics stored somewhere?

[miklb]

Only for the map site. At peak of Florence I saw ~1000 unique visits per day. I’ll see if the distribution map stats are different

[nihonjinrxs]

@omnilord Does #83 review/fix any of this, or just refactor what's there?