Added a new MetricType Average. Metrics with that type will (generally) use .Add() instead of .Increment() to add new values to the metric. Examples might be # of bytes or duration of an operation. Every period (60s) the average will be reported to StackDriver. For example, if the values 10, 10, 100 were tracked then (10+10+100)/3 = 40 would be reported.
Removed the dependency on log4net. By default errors will be written to the console. Allow clients to specify how they want to log failures via the IFailureCallback.
Incremented to 0.4.0