Routing tests

Endpoints for poking at status codes, redirects, timeouts, and payload sizes.

• GET /status/:code — respond with any HTTP status. /status/418
• GET /redirect?to=/health — 302 redirect. try it
• GET /delay/:ms — respond after a delay (max 30000ms). /delay/1000
• GET /bytes/:n — return N bytes of payload (max 10MB). /bytes/1024
• ALL /echo — reflect the request. /echo