upgrade build

upgrade to Scala 2.10.2; metrics 3.0.1; play 2.2.1
remove incorrect laziness

Pervasive use of lazy val leads to users of com.kenshoo.play.metrics.MetricsRegistry holding on to stale references. Play’s reloading application loads external libraries in a class loader that will not refresh on reload, so a lazy object with lazy vals will hold on to the metric registry that was created on initial app load, while the plugin will create a fresh metric registry upon each app reload!

‘def’ must be used in favor of ‘lazy val’ to ensure that the latest registry and configuration is accessed every time, even after an app reload occurs.

The bad behavior can be exposed when instrumenting the initialization code block for lazy vals to see exactly when initialization occurs and exactly what object has been stored.
Merge pull request #2 from dwhjames/topic/laziness