include node_modules so release .zip is deployable

node_modules/cross-fetch/dist/node-polyfill.js

@@ -0,0 +1,11 @@
+const fetchNode = require('./node-ponyfill')
+
+if (!global.fetch) {
+  const fetch = fetchNode.fetch.bind({})
+
+  global.fetch = fetch
+  global.fetch.polyfill = true
+  global.Response = fetchNode.Response
+  global.Headers = fetchNode.Headers
+  global.Request = fetchNode.Request
+}