The configurable boosts feature can case other unit tests to fail if a
user has customizations in their `pelias.json`.
This adds proxyquire to all tests that might be affected, which force
the default config, preventing such failures.
This was missed by me when working on https://github.com/pelias/api/pull/580, but caught by the acceptance tests!
Unfortunately it was caught after going to production.
Using the check-types module, check that lat/lon values are numbers,
instead of checking their truthyness, to ensure that queries for null
island work correctly.