Outage Anniversary

This adds a new feature that creates a page where you can see if there were any events on the same date as today.  This can be a fun way to revisit learning from past post-mortem and spread knowledge around.

To make this happen I added some extra functionality to Configuration and tweaked the way views get included onto the 'page' and 'edit' views. I also set up a global nav bar and way to add features to it.  #EtsyHackweek2014

would need a feature block like:
```
    { "name" : "anniversary",
      "enabled": "on",
      "navbar" : "on"
    }
```