Finished refactoring of MongoClient and MongoOperations.  There is now a single implementation of MongoClient, MongoClientImpl, that is constructed with a MongoConnection (formerly MongoOperations).  The inner classes of ReplicaSetMongoClient, SingleServerMongoClient, and SingleChannelMongoClient have been pulled out into top-level classes that implement MongoConnection.
Refactored SingleServerMongoConnection so that subclasses are no longer required.  Instead, it's constructed with an instance of SimplePool<MongoPoolableConnection>. MongoPoolableConnection is implemented by the sync and async variants of single channel mongo connection.
Just a bit of simplification in SingleChannelSyncMongoConnection and MongoChannel
Rationalized method names and parameter names in MongoConnection and MongoAsyncConnection
Fixed Mongo constructor to properly pass along server address seed list.