Start RAssertDolphin (#3)

* Start RAssertDolphin

* Add OSContext

* Add missing files, Prime2's ErrorHandler

* Progress in ErrorHandler

* comments

* Don't link new code

* Format code

* Slight adjustments

* Use u16 for OSError

Former-commit-id: 7e8bc34cab

include/dolphin/os/OSError.h

@@ -0,0 +1,19 @@
+#ifndef __OSERROR_H__
+#define __OSERROR_H__
+
+#include <types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef u16 OSError;
+typedef void OSErrorHandler(OSError, OSContext* context, ...);
+
+void OSSetErrorHandler(OSError code, OSErrorHandler* handler);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif