dev-api: add developer portal, OpenAPI spec, and Flatenbadet case study

- New /developers/ page with API docs, SDKs, pricing, use cases
- OpenAPI 3.0 spec for Orders, Missions, Photos, Analytics
- Case study: Glasskiosken i Flatenbadet — complete ROI analysis
- Updated /order/ with recurring missions and frequency dropdown

services/frilans-payout/node_modules/run-parallel/index.js

@@ -0,0 +1,51 @@
+/*! run-parallel. MIT License. Feross Aboukhadijeh <https://feross.org/opensource> */
+module.exports = runParallel
+
+const queueMicrotask = require('queue-microtask')
+
+function runParallel (tasks, cb) {
+  let results, pending, keys
+  let isSync = true
+
+  if (Array.isArray(tasks)) {
+    results = []
+    pending = tasks.length
+  } else {
+    keys = Object.keys(tasks)
+    results = {}
+    pending = keys.length
+  }
+
+  function done (err) {
+    function end () {
+      if (cb) cb(err, results)
+      cb = null
+    }
+    if (isSync) queueMicrotask(end)
+    else end()
+  }
+
+  function each (i, err, result) {
+    results[i] = result
+    if (--pending === 0 || err) {
+      done(err)
+    }
+  }
+
+  if (!pending) {
+    // empty
+    done(null)
+  } else if (keys) {
+    // object
+    keys.forEach(function (key) {
+      tasks[key](function (err, result) { each(key, err, result) })
+    })
+  } else {
+    // array
+    tasks.forEach(function (task, i) {
+      task(function (err, result) { each(i, err, result) })
+    })
+  }
+
+  isSync = false
+}