develop/ktcc: Post-SVN tidy

- Move source code from `trunk` into program root directory.
- Update build files.

programs/develop/ktcc/libc.obj/source/stdio/vsnprintf.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+int vsnprintf(char* buffer, size_t count, const char* format, va_list va)
+{
+  return _vsnprintf(_out_buffer, buffer, count, format, va);
+}