Update ioredis version

services/document-updater/package.json

@@ -10,7 +10,7 @@
     "async": "2.0.0-rc.5",
     "coffee-script": "1.4.0",
     "express": "3.3.4",
-    "ioredis": "^2.0.1",
+    "ioredis": "^2.2.0",
     "logger-sharelatex": "git+https://github.com/sharelatex/logger-sharelatex.git#v1.0.0",
     "lynx": "0.0.11",
     "metrics-sharelatex": "git+https://github.com/sharelatex/metrics-sharelatex.git#v1.0.0",