[WIP] Add support for events (#60)

* Add support for events, move concept of domains to IpcService

* Support waiting for KThread, remove some test code, other tweaks

* Use move handle on NIFM since I can't test that now, it's better to leave it how it was

Ryujinx.Audio/ReleaseCallback.cs

@@ -0,0 +1,4 @@
+namespace Ryujinx.Audio
+{
+    public delegate void ReleaseCallback();
+}