Determine what issues jetlag might have creating large clusters

[akrzos]

We attempted to deploy a large cluster today via Jetlag and ran into at least one issue in which the discovery image generation would take longer than 30s (The default timeout for the URI module in Ansible).

We should:

• Document in the troubleshooting and/or tips document limits to larger clusters (Seems that larger than 25 nodes will result in this timeout)
• Bump the timeout either by default to something much larger or bump only when above a specific threshold of nodes
• See issue #141 and see if the image generation service fixes this problem