stat and log rate limit data where available
stat and log rate limit data where available

It doesn't log the IP information on its rate limit. IP is considered
personally identifiable information and against our policies to log.

Fixes #1120

jcjones/boulder,jcjones/boulder,r0ro/boulder,mehmooda/boulder,jsha/boulder,sophie-h/boulder,benileo/boulder,jcjones/boulder,bmw/boulder,hlandauf/boulder,benileo/boulder,letsencrypt/boulder,lucasallan/boulder,ibukanov/boulder,ZCloud-Firstserver/boulder,sophie-h/boulder,hlandauf/boulder,jfrazelle/boulder,letsencrypt/boulder,lucasallan/boulder,ZCloud-Firstserver/boulder,patf/boulder,benileo/boulder,r0ro/boulder,ZCloud-Firstserver/boulder,lucasallan/boulder,jfrazelle/boulder,r0ro/boulder,ibukanov/boulder,benileo/boulder,jfrazelle/boulder,mehmooda/boulder,r0ro/boulder,bmw/boulder,jfrazelle/boulder,jcjones/boulder,jsha/boulder,bmw/boulder,ibukanov/boulder,patf/boulder,jsha/boulder,mehmooda/boulder,sophie-h/boulder,patf/boulder,mehmooda/boulder,ZCloud-Firstserver/boulder,hlandauf/boulder,patf/boulder,hlandauf/boulder,letsencrypt/boulder