The generated code for Bus.Send, Bus.Reply and Bus.Publish now uses lambda expressions.

- Removed the need for having pascal or camel case variables for the Bus API operations. Relates to #294 
- Fixed the casing for the dialog title "User code changes required"
- The message is fully namspaced as before when newing up the var to avoid compiler errors, if the using hasn't been resolved.. 

So, auto generated code for `Bus.Send` will look like this:
```c#
        partial void HandleImplementation(SubmitOrder message)
        {
            // TODO: SubmitOrderHandler: Add code to handle the SubmitOrder message.
            Console.WriteLine("Sales received " + message.GetType().Name);

            // TODO: Add code inside the lambda to fill in the message properties.
            Bus.Send<Application18.InternalMessages.Commands.Sales.ApproveOrder>(m => { });
        }
```
 
Autogenerated code for `Bus.Publish` will look like this:
```c#
        partial void HandleImplementation(OrderReceived message)
        {
            // TODO: OrderReceivedHandler: Add code to handle the OrderReceived message.
            Console.WriteLine("Billing received " + message.GetType().Name);

            // TODO: Add code inside the lambda to fill in the message properties.
            Bus.Publish<Application18.Contracts.Billing.OrderBilled>(m => { });
        }
```

The user code changes required dialog will also prompt the user with the lambda code.

cc/ @andreasohlund @esculli