Revamp code generator

[michaelklishin]

We've been avoiding tweaking code generator much in recent years because it's fairly hard to make non-trivial changes. As a result it is much harder to refactor the rest of the library because we depend on the existing ModelBase hierarchy and responsibility scope heavily.

Now that we require .NET 4.0, we can investigate Expression Trees. The idea of using F# has came up a few times in the past (for templating, implementing ModelBase in F# and relying e.g. on Code Quotations will likely suffer from the law of diminishing returns in our case).

Specific points of improvements we should aim for:

• Make it easier to make changes to ModelBase
• Split generator ModelBase into smaller parts
• Make generated code better suited for future API and implementation changes, e.g. in WinRT/Windows Store support #16 and Named parameter version of the API #20.

Since the code generation artefacts are not exposed to end users, we can make breaking changes there but preserving .NET and Mono compatibility is a must.

[YulerB]

Is the idea to use T4?

[YulerB]

Or something like this:

client
/* Expressions built from here. */
  
	.ConfigureHosts(Expression<Func<IEnumerable<EndPoint>> host)

	.GetCluster(Expression<Func<string>> host)
	.GetLocalEndpoint()
	.GetNearestClusterEndpoint()

	.Heartbeat(Expression<Func<int>> frequency)
	.VirtualHost(Expression<Func<string>> vHost)
	
	.AuthenticatePlain(Expression<Func<NetworkCredential>> cred)
	.AuthenticateCertificate(Expression<Func<X509Certificate2>> cert)			
	
	.FailoverAutomaticly() /*Default to not fail-over automatically */
	.RecoverTopology() /*Default to not recover the topology*/

	.DirectExchange(Expression<Func<string>> exchange)
	.FanoutExchange(Expression<Func<string>> exchange)
	
	.AutoDeleteQueue(Expression<Func<string>> queue)
	.DurableQueue(Expression<Func<string>> queue)
	
	.SetDeadLetter(Expression<Func<string>> exchange, Expression<Func<string>> queue)

	.SetMessageQualityOfService(Expression<Func<int>> messages)
	.SetMessageSizeQualityOfService(Expression<Func<int>> bytes)
	
/* execution occurs on these methods. */

	.Publish(SendMessage message)
	.BatchPublish(IEnumerable<SendMessage> messages)
	.PublishWithConfirm(SendMessage message)
	.BatchPublishWithConfirm(IEnumerable<SendMessage> messages)

	.GetStatistics()
	.GetMessage()
	.PurgeQueue()
	.DeleteQueue()
	.ForwardTo(string exchange, string queue)

	.ConsumeAsync(Func<Task, ReceivedMessage> consumer)
	.Consume(Action<ReceivedMessage> consumer);

connection
	.ConnectTo(Expression<Func<EndPoint>> host)
	.SetLittleEndian()
	.SetBigEndian()
	.UseSSL(Expression<Func<X509Certificate2>> cert)

	.ConsumeAsync(Func<Task, Frame> consumer)
	.Consume(Action<Frame> consumer)
	.HandleFramesAsync()
	.HandleFrames()

[lukebakken]

Labeled for net-gen client and closing.