chore(package): update @types/meteor to version 1.4.21

Closes #317

Author: greenkeeper[bot]

package.json

@@ -15,7 +15,7 @@
     "@types/dockerode": "^2.4.6",
     "@types/file-saver": "0.0.1",
     "@types/lodash": "^4.14.68",
-    "@types/meteor": "1.4.8",
+    "@types/meteor": "1.4.21",
     "@types/node": "^8.0.15",
     "@types/node-cache": "^4.1.0",
     "@types/node-fibers": "0.0.28",