Speed up response

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As a developer of an application that uses the Validator API,
I want to get responses quickly
so that I can provide information to my users in a timely fashion .

In IATI/ckanext-iati#417 we're discussing using the Validator API to power a summary view of publishers.

In my testing this afternoon, the API seems to take 300-400ms to return results for a single file; this seems to be regardless of response size as both a 2kB and 40kB response took the same amount of time. This is fine for a single response, but in the use case we have in mind, it might be necessary to make tens or even hundreds of requests. Obviously these can be cached by the consuming application but even with moderate churn, this could be quite slow.

Alternatively, of course, we could look at offering bulk querying.