Upgrade to Dropwizard 0.7.0 + Java 1.7

This is a relatively large change.  Most of it should be really straightforward to review as mechanical changes to import and use com.codahale and io.dropwizard versions of things.

There are 2 non-mechanical changes though.  The biggest is with metrics usage.  A lot of changes went into Metrics 3, and it caused our Metrics.java to change quite a bit.  I had a lot of trouble deciphering the various cases of logic within Metrics.java so I split it up into two pieces, Metrics.ClassMetrics and Metrics.InstanceMetrics depending on whether or not we're generating metrics for a class that operates on many different services at the same time or an instance that operates on a single service.  Hopefully this change is clear -- as a result of this I split up the MetricsTest.java into two pieces as well.  A couple of tests got dropped along the way because I don't *think* they're relevant anymore, but I might be mistaken.

The other change is mostly to the examples and it's upgrading them to work with Dropwizard 0.7.0.  For the most part things aren't complicated, resources get registered slightly differently, etc.  The one tricky thing was figuring out the http port for the primary web server as well as the http port for the admin service.  Those have gotten much harder to determine.