fixes 163 - clean certificate only when a new build request starts

fixes #151 - add show host page
Added a nested link to hosts to lots of controllers

added basic pagination

fixes #159 - query interface should be able to limit host selection based on state

fixes #159 - If facts are imported incorrectly or incompletely, the Statistics links does not work

refs #153 - this will send email notifications only if its enabled in config/settings.yml

updated to year 2010

Merge commit 'github/master'

fixes #153 - EMail Notifications when hosts report failures

fixes #157: Audit show page might fail