Updated SoundRecorder to support multiple input devices

[zsbzsb]

And if you decide to mention that sfSoundRecorder_getDevice returns an IntPtr instead of a string that is required. Otherwise the interop will free our static string causing a crash on next call. And yes it has been fully tested.

http://elegantcode.com/2010/11/17/the-black-art-of-pinvoke-and-marshaling-in-net/

Doing some more research on marshaling strings, I found out that in case the native function does its own cleanup, an IntPtr must be returned by the C# prototype declaration instead of a String.

[LaurentGomila]

And if you decide to mention that sfSoundRecorder_getDevice returns an IntPtr instead of a string that is required.

I don't care since it remains an internal detail.

But shouldn't GetDevice/SetDevice be a Device property instead?

[zsbzsb]

setDevice returns a bool indicating if it was successful.

[LaurentGomila]

Ah, right.