Nested query params

[dazld]

Currently, nested query params (type Object in the docs) are output directly as clojure literals to the query string, meaning that the stripe API sees a query-params argument of

{:active true
 :currency "GBP"
 :recurring {:interval "month"}}

... like this:

{
  "active": "true",
  "currency": "GBP",
  "recurring": {
    "interval": "{:interval \"month\"}"
  }
}

... which understandably returns a 400 bad request.

The build-query-params function should correctly handle nested maps, and produce values such as:

foo=1&bar[baz]=2 for an argument of:

{:foo 1
 :bar {:baz 2}}

I'm not sure how many levels of nesting the Stripe API may require.

Here's an example where it currently breaks:

(->> (prices/list-all {:query-params {:type "recurring"
                                      :currency "GBP"
                                      :recurring {:interval "year"}
                                      :active true
                                      :limit 10}}))