Allow sounds to be loaded from byte arrays on game thread

[tomcashman]

I/O blocks the game thread so ideally there would be a way to read the byte data on another thread and then pass that to the game thread to construct the sound (sounds need to be constructed on game thread due to JNI).

Check if this is possible on android/iOS/MonoGame

Alternatively, have a method that returns a Future which loads data asynchronously from a FileHandle