Validating curl and Node implementations for WePay

In particular the Node version will produce output like the following:

jwalsh:app/ (master✗) $ node checkout.js
{"checkout_id":2100187472,
 "checkout_uri":"https:\/\/stage.wepay.com\/api\/checkout\/2100187472\/4d2ad7f7"}

while the shell call looks like

jwalsh:SAMA-119_wepay_prototype/ (master✗) $  ./bin/api-checkout.sh
{"checkout_id":968234827,
 "checkout_uri":"https:\/\/stage.wepay.com\/api\/checkout\/968234827\/19348777"}
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