Add Ratelimit parameters to /info

We previously registered with no parameters, added parms so they
are displayed as follows (example):

"ratelimit": {"max_sleep_time_seconds": 60.0,
"container_listing_ratelimits": [[0, 100.0], [10, 50.0], [50, 20.0]],
"container_ratelimits": [[0, 100.0], [10, 50.0], [50, 20.0]],
"account_ratelimit": 1.0}

Note that not all parameters are exposed (intentionally) via /info

Change-Id: I36c7ef15af17e3eb8ebb93429035bd06d089a945
Closes-Bug: 1308989
Merge "Add Ratelimit parameters to /info"